Resignings: Flexibility in team construction

Peters, Cooper, Kelce, Maclin….ALL good moves, but don’t misread them.  One of the most important aspects of team construction (when you’re essentially starting from scratch), is maintaining flexibility for as long as possible.  That sounds easy, but it requires a lot of discipline.  It means being brutally honest with yourself as to the true quality of the roster and it often means getting ripped by beat writers for a year or two.  As of right now, Howie appears to be doing this perfectly.

Remember last offseason?  The team signed James Casey to play TE (well to play a couple of different roles).  The team signed Isaac Sopoaga to play NT.  The team signed Patrick Chung and Kenny Phillips to play S.

After that haul, what did the Eagles then do in the draft?   They drafted a TE (Ertz), a NT (Logan), and a S (Wolff).  Granted, Wolff wasn’t expected to play much, but the overall point is:  FA and the draft serve two very different purposes.  Free agency is for filling holes in the roster, the draft is for adding talent.  Even though the Eagles re-signings weren’t like the Free Agency deals we typically think of, they still fall into that category.

Heading into free agency, the goal of any team must be to fill any huge gaps in the roster.  If you think back to the color chart I posted last week, this means identifying the “red” areas and trying to upgrade them to “yellow”.  Those types of acquisitions aren’t the headline-generating deals, but they’re extremely important!  If you don’t fill the gaps in FA, you’re left with just two potential outcomes:

1) You have to draft somebody relatively early in the draft at that position, regardless of it he’s the BPA.

2) You go into the season with a huge gap in the roster.

Both of those outcomes are terrible, and the only way out is to get lucky in the draft and have the BPA coincidentally be the position you need.  Of course, it almost never happens that way.  Instead, you end up taking a 26-year-old Guard in the first round….

I want to make this abundantly clear, so let’s conceptualize it a bit:

Imagine you’re a team with identified NEEDS at SS, CB, DE, OT.   What’s your free agency plan?  Many fans would look at that situation and hope for the team to sign a top-end starter at 1-2 of those positions (the unreasonable fans might hope for all 4).  However, there’s a big problem with that strategy.

Namely: You don’t know who is going to be available for you in the draft.

There are two main methods of roster construction, free agency and the draft.  Free agency has no uncertainty.  The draft has a LOT of uncertainty.  The problem with that is free agency occurs BEFORE the draft.  The interplay between these two processes is tricky, and many people don’t properly connect the two when analyzing them.

Going back to our pretend team, let’s say we’ve got the 8th pick in the draft.  What are the odds that the best player available (or a player in the top remaining tier) is a SS, CB, DE, or OT?   Pretty damn good.  Now let’s say you signed a starting CB and DE in the draft. free agency.

Now your “needs” are SS and OT.  What are the odds that the BPA at your pick in the draft will be a player at one of those positions?  Decent, perhaps, but A LOT LESS than they were when you also “needed” a CB and a DE.

By filling the starters roles in free agency, you made it LESS likely that you’ll find a starting quality player at a position of need in the draft.  That’s the important takeaway.  Remember that given the salary cap, the new CBA, and the auction dynamics involved in free agency, finding a quality starter in the draft is MUCH more valuable than finding one in free agency.

The optimal draft strategy is to take the BPA and move up and down in the draft whenever there is a serious dislocation in value.  To do that, though, you need to have all of your gaps filled BEFORE the draft.  Not necessarily with star players, but with guys who can at least pass for mediocre.  Otherwise, you either reach for a non-BPA player, and likely ruin the pick, or you go into the season with a glaring hole.

So, teams that are still in the construction phase, and not yet ready to seriously contend (like the Eagles right now IMO), need to be VERY careful about signing star players in free agency.  Instead, the team should use free agency to fill those holes, and when the roster IS at or very close to contending, THEN you use free agency to put the final 1-2 pieces int place.  At that point, you’ve lost flexibility anyway, and what you NEED is certainty.  Until then, though, it makes no sense to play around in the top-tier free agent market.

With that, let’s talk about a couple of deals:

Jason Peters: Convenient timing for this signing, as I’d just said that the Eagles need to think about replacing Peters soon.  Does the extension mean they disagree?  No, though it suggests they think it might take 1-2 years longer for Peters to decline than I had projected.   Note my projection was admittedly a guess and not backed up by any research into the aging trends of left tackles.  However, I assure you that the Eagles are not banking on Jason Peters being the starting LT in 2018.  He signed for $38.3 million….but only $19.55 million of that is guaranteed.  Also, the guaranteed portion flames out quickly, and after next season the Eagles will be able to cut him with very little $ impact.

Basically, the Eagles bought themselves a call option on the downside of Jason Peters’ career.  If his play declines quickly, they can cut him loose.  If he continues to be an elite LT, they’ve got him locked up at a reasonable level.

Cooper/Maclin: This goes right to the heart of what I was saying above.  If you let BOTH walk, you’ve got a big need at WR.  You either sign someone in free agency or head into the draft knowing you need a WR who can contribute immediately.  Instead, the Eagles signed both of them, to reasonable deals (again, you should only really care about the guaranteed money).  That means the Eagles don’t “need” to draft a WR early.  However, it also doesn’t mean they won’t.  What they’ve done is given themselves the flexibility to take a WR if he’s the BPA, while also allowing them to pass on the WR if he’s not.

Like I said, Roseman is already having a great offseason, but don’t let the beat writers mislead you.  These contracts (Peters and Cooper especially) are nothing more than reasonable call options that give the team flexibility going forwards.  Neither player is guaranteed to be here beyond 1-2 more seasons.  So don’t be shocked if the Eagles take an OT or WR in the first three rounds.

State of the Roster: Building over time

Last year I provided illustrations, by color, of the Eagles offense and defense, using it to identify weaknesses and strengths.  Today I want to take that to the next level, for two main reasons.  First, PFF is now providing the same visuals.  Maybe they did this before and I didn’t know about it, but in any case, there’s no reason for me to duplicate what they’ve already done.  Here is their projected line-up.  Clicking it will take you to the source write-up.

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The second, and more important, reason that I want to do things differently is because the above chart misses out on a vital aspect of team construction.


You can’t sustain success if you’re entire focus is the next season.  The team needs to be built so that it can contend OVER TIME.  Given how much luck there is in the game, it makes more sense to contend over a long period of time rather than “go for it” in any one season.  Andy Reid’s Eagles did this perfectly, they just never had things fall the right way.

This is particularly important for the Eagles because of where the team is currently in its team-building process.  I mentioned in my last post that there are still a lot of holes, and some people pushed back.  While there’s plenty of room to disagree over the projected quality of each player, I realized we first have to agree on just what timeframe we’re looking at.

For example, if we are just considering next season, than Jason Peters is far from a “hole”.  However, if we’re looking at creating a 3-4 year “window” of contention, then things become a bit more difficult.  Peters is 31 years old.  Do you think he’ll still be an above-average OT in his mid 30s?  It’s possible, but the point is that it’s not enough to just look at this coming season.

The question then becomes:  What’s the best way to alter the graphic above to incorporate longer time-projections?

Today I’ll take a stab at that.  First, though, I want to note that the goal is obviously to build a team that contends for a lot longer than 3-4 years.  However, we have to recognize the limitations, or margin of error, in any attempt to project future performance.  The farther out we go, the less accurate or predictions will be.  Therefore, once we go out to 5+ years, there seems to be very little value in attempting to projecting player performance.  That might not be right, but it’s the constraint I’m operating within for right now.

So….the projections:

As you’ll see below, I simply listed every starting player on offense and defense, then assigned them a color based on how I believe they will perform in the relevant year.  For now, we’re going very low-resolution, so I’ve separated players into just 3 groups.  Red is below-average/bad, yellow is average/mediocre, green is above-average/objectively good.  There’s definitely room to refine this (McCoy could be blue, as PFF did above), and I’ll do so after FA and the draft.

The Offense

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As you can see, I also included the salary cap numbers, mainly to show when players’ contracts were up.  Overall, the offense looks pretty good.  There are just 2 areas that could use some immediate improvement, RG and the TE/WR situation behind D-Jax.  Of course, if Maclin resigns and comes back healthy, he could easy go “green” for the foreseeable future.  That would help a lot.  Still, though, the offense looks like it’s in really good shape.

The concern comes in year 3.  As illustrated, Peters, Mathis, and Herremans are all in their 30’s, and while they can certainly perform at a high level into their mid-30’s, we have to ask ourselves:  what are the chances of that happening?  Moreover, what are the chances that all 3 of them do so?  Slim, at least in my opinion.  That’s why I really wouldn’t be upset to see the team add an OL in the draft (beyond the 7th round OL the team should be drafting every year, but that’s a different issue).

I certainly anticipate Zack Ertz moving into the starting TE role, and being a good player for a long time.  Notice, though, that still leaves a whole in the roster.  Anyway you cut it, the offense has space for another receiving weapon.

The Defense

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Now we get to the fun part, the defense.  It won’t shock anyone to learn that the defense has a lot more holes than the offense.  There are some tough calls to make here, as far as projections go.  Can Earl Wolff go “green”?  Yes, but I think the odds still favor him being just OK as a starting safety.  Similarly, some people will probably argue that Bennie Logan deserves a better rating.  Again, its possible, but I’m not convinced.  Additionally, it’s very harmful to the construction process if you assume guys will hit their “ceiling”.  Many don’t, or rather their ceiling gets adjusted downwards as their career progresses.

Most notable here is the lack of good players in the secondary.  Boykin might be able to slide over to the #1 or #2 CB spot, but that still leaves a hole to fill.  Also, remember not to focus on just the first year.  Look at year 3 above.  Naturally, the team has a few offseason to address the issues, so their not urgent, but it has to be accounted for.  Demeco Ryans isn’t getting any better, and how much longer do you think Trent Cole can play effectively for?

You surely noticed the thick black box in both graphics above.  That’s what I’m looking at as the “strike zone” for this team.  If I’m Howie Roseman, I want to turn as many of those boxes green as I can, even if it’s at the expense of next season.  Also, I want to eliminate every red box.  This is what I mean when I mention accounting for time.  You’re not just trying to build the best team you can.  You’re trying to get a lot of different pieces to fit come together at the right time.  It won’t work if your young players improve to “good” just in time for your veterans to decline.

Again, some more work to be done here, and I’m hoping to do a little research into the general career arcs of different positions (so we know things like what age an OT should be expected to decline).  Keep this in mind though when you hear about potential FAs.  How well to they fill those boxes?

Initial Offseason Needs

We’re in the midst of the offseason lull and draft coverage will ramp up soon.  Therefore, it’s a good time to take a high level look at the roster and see what the team’s “needs” are.  Having that framework makes following free agency and the draft much easier (and useful).  One big point before we begin:

This year feels completely different from last year (at this time).  However, that doesn’t mean the goals aren’t very similar.

One year ago, the Eagles looked like a complete mess, and appeared to be at the very beginning of a long rebuilding process.  At least that was the message you got from reading most beat writers.  Readers here obviously knew that things weren’t quite that bleak.  This year, the general Eagles vibe seems to be that it’s a team that has already “rebuilt”, and are now ready to take the next step towards contending (perhaps not competing with Seattle and San Fran next year, but certainly solidifying a place just behind them).  From my point of view, that’s a bit aggressive.

The team took a huge step forward this season (I will probably refer to 2013 as “this season” until FA starts).  Most important was the hiring of Chip Kelly.  However, a number of players emerged as potentially significant contributors to a contending team.  Specifically, Boykin, Lane Johnson, and Zach Ertz all seem to be somewhat reliable pieces that either weren’t with the team last year or still carried a lot of uncertainty (Boykin).  Johnson and Ertz both had issues, but given the totality of their performances, I think the odds are very good that both will become strong starters.

While that certainly helps, we can’t let it blind us to the fact that the team still has a lot of weaknesses.  The defensive roster is still very much in flux or just plain bad.  Most glaring is the lack of talent and depth in the DB corps.  However, the LBs aren’t good either and the DL has some holes as well.  Special teams was atrocious for parts of last year (outside of Donnie Jones), and the kicker probably needs to be upgraded at some point in the near future.  On offense, the scheme obviously works, but Jason Peters and Evan Mathis are getting old, and the WR group is thin and could use some more high-end talent.  LeSean McCoy, the Eagles MVP and the guy the offense is built around, is a unique talent.   If he were to get injured, the consequences for the offense could be catastrophic.

So…in light of all that, what should the Eagles do?

I’ll go through position groups in more detail later, but for now let’s just focus on a few big priorities.

1)  Add talent – This seems so simple, yet it gets glossed over far to quickly by most people.  Did you watch the Seahawks this year? Did you watch the Broncos?  If the answer is yes, then you must have realized that those teams operated on a much higher level than the Eagles did.  Until the Eagles become a “contender”, first priority is to add talent whenever and wherever possible, within the structure of the team of course.  So that doesn’t mean go out and buy every FA available.  It does mean the team should be flexible and agnostic as to what positions it looks to upgrade.

If it were me, I’d go through every FA, under the age of 28, in the league and see where they would slot on the Eagles depth chart.  If they’re an upgrade, I make them an offer.  If that ends up just getting you a handful of 3rd stringers, so be it.  Fans don’t get excited about those type of signings, but they’re really important, especially in the “build” phase.

2) Backup QB – This has to be a high priority.  Michael Vick is gone, he no longer makes sense for the team.  As we saw last season, QB depth is vital to any team looking to make the playoffs.  It’s extremely rare to find someone who can step in and take your team to a title (Brady and Warner were anomalies).  However, you do need someone who can step in and win a few games.  Again, not a sexy position to upgrade, but if Nick Foles goes down for 2-3 games next season, it could cost the team a playoff spot.  When the FA class shakes out a bit, we can look at potential targets here, but it’s HEAVILY dependent on the contract.  As far as traits go, I just want someone who is competent and DURABLE.  I’d gladly sacrifice a bit of talent for durability.  As I said, you’re almost definitely not winning the title with a 2nd string QB anyway, so the extra talent isn’t going to get you much.  Meanwhile, an injury to the 2nd string QB can be a season-killer, as it nearly was for the Eagles this year.

3) DBs….a lot of them – No position group on the team is as weak as the DBs.  The CBs are OK, but each of them seems better suited to a #2 role.  The Safeties are a bigger concern, obviously, and you can’t count on the draft to fix them.  A lot of fans are hoping for a Byrd signing here, but I think it’s too early for a move like that.  Rather, I’d look to sign 2-3 mid-level guys to reasonable deals and see which ones stick.  That’s a similar approach to last season.  Kenny Phillips and Patrick Chung didn’t pan out, but they didn’t cost the team anything either.  Hopefully the BPA when the Eagles pick in the draft is a DB, but you can’t count on that.  In the meantime, keep adding low-risk players and try to make incremental improvements.  That way, when you do find the #1s, the rest of the depth chart is already in place.

4)  LBs – Similar story to the DBs, but for slightly different reasons.  The Eagles LB corps last season was serviceable, and occasionally very good.  Unfortunately, they’re not likely to stay that way.  Demeco Ryans is obviously not a long-term solution, neither is Trent Cole.  I still don’t see Brandon Graham as a viable starter either (in this defense).  That’s a lot of holes to fill, and it’s not going to be done in one offseason.  If the team can plug one of those two spots with a long-term guy, even if he’s just above-average, it will have taken an important step.  The rush LB will draw most of the attention this offseason, but don’t forget about Demeco’s spot.

5)  The Offense – This ties into the first priority, adding talent.  Most of the focus will be on the defensive side of the ball, and for good reason.  However, it’d be a BIG mistake to forget about the offense.  Remember, an above average offense is a NECESSARY condition for winning the SB.  The same cannot be said of the defense.  The Eagles’ offensive position is more precarious than it might seem.  The WR corps is thin, even if Cooper or Maclin return.  One injury to D-Jax and suddenly the group looks like a weakness rather than a strength.  McCoy is also a HUGE risk factor.  The offense is built around him, and the fact that he is so good means there’s just no way to adequately replace him if he goes down.  Another weapon or two would help alleviate that risk.

Lastly, Jason Peters is now 32 years old.  Evan Mathis is 32 years old.  Todd Herremans is 31 years old.

Moral of the story here is that nobody should be surprised if the Eagles take an OT in one of the first two rounds this year.  If that’s the BPA, I have absolutely no problem taking an OT in the first round, even if he sits a year behind Peters (or Johnson before he switches sides).

As I said, I’ll take a much more detailed look at the roster soon, and I think I’ve come up with a good way to visualize things.  In the meantime, be hopeful, but realistic.  There are a LOT of holes in this team, and barring an amazing draft, it’s going to take more than one offseason to fill them.

Break from Football for a Good Cause

You may have noticed that I’ve been posting less often over the past few weeks.  I’ve been swamped with other projects and school.  Fortunately, some of that is clearing, so I’ll have more time to get back to the Eagles.  First, though, I wanted to briefly talk about one of the things I’ve been working on.

As part of the Penn Law curriculum (which is not altered at all for JD/MBAs), every student has to complete 70 hours of pro bono work.  I’ve chosen to fulfill my requirement by volunteering with the Iraqi Refugee Assistance project.  Over the past few months, I’ve been working with a client in Baghdad, helping him and his family apply for resettlement in the U.S.   He and his family have been the victims of severe persecution (attacks, kidnapping, threats, etc…) and have no other choice but to flee the country.  As you can imagine, the red tape involved in U.S. resettlement is immense; that’s where we come in.

This March, six other students and I will be traveling to Kurdistan (Northern Iraq) to conduct in-person interviews with Syrian and Iraqi refugees.  To that end, we’ve started an online fundraising drive to help cover the costs (flights to Erbil ain’t cheap).  If you can help out, please do.  If not, no worries, but at the very least, please watch the video below.  Awareness is a big part of the problem, so just taking 3 minutes to learn more about the situation is helpful as well.  UPDATE:  Video below is not my client, he’s just a good example of the type of people we’re helping.

Help Out

Thanks in advance.  I promise this won’t become a habit (I think this is the first non-sports post I’ve done actually), and I’ll get back to the Eagles soon.

– Brent

Roster Building with Seattle: Skill, luck, or something else….

So Seattle just stomped Denver in the Super Bowl.  Game sucked, commercials sucked, RHCP played air-guitar/bass.  At least Bruno Mars came through.  I didn’t really see anything particularly interesting to discuss from the actual game, other than to note that Pete Carroll made some very poor strategic decisions early on (the 4th down calls).  Of course, if he thought his team was much better than Denver’s (and it appears that was the case), then taking the points may actually have been the right call.  Remember, favorites want low variance.  Refer back to here.

I did, however, see something interesting when looking at Seattle’s roster composition.  Specifically, the great defense the team has put together is composed of players who were drafted with relatively low picks.  Here’s are the starters, plus Cliff Avril:

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Two 1st round picks, neither from the top 10, and one 2nd round pick.  What you’re seeing there is an incredibly efficient use of draft resources.  The vaunted secondary features two 5th round picks, a 6th round pick, and Earl Thomas.

If this isn’t surprising you, remember that elite players come mainly from the 1st round of the draft, and almost entirely from the first two rounds.  See this chart from the archives:

So…it looks like what the Seahawks managed to do (build a historically good defense with low-round picks) should be extremely difficult, if not impossible. Let’s take a look.

First, how good were the Seahawks this year?

I’m going to use a shortcut here, and rely on just points allowed adjusted for league average.  This measure isn’t perfect because it doesn’t account for the contributions from the offense and special teams, but it also relies on readily available data, and more importantly, doesn’t offer a lot of false positives.  Since 2000, here are the best teams by this measure, with Seattle added to the mix:

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The teams highlighted in yellow won the Super Bowl.  I should also note that this year’s Carolina Panthers just missed the list.  They allowed 35.6% fewer points than average.

Anyway, as you can see, Seattle was historically good this year at preventing points.  Now, how does their roster compare?  Well I looked at the starting rosters, according to, of the 5 teams ranked ahead of them (haven’t had time yet to look the rest).  Here’s what I found:

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Most of those teams seem to line up with our expectations; the best defenses ever feature a lot of 1st round picks.  I realize that not all of these players were drafted by the teams they ultimately played for above.  That’s a secondary matter, though, and one we can explore separately.  For now, I’m just interested in where the talent originally came from. It’s not enough just to count up 1st rounders.  We want a complete comparison that accounts for the differences in the value of each pick.  To do this, I used the Draft Pick Value Chart.  This is the chart teams either use or used to use as a guideline for weighing trades.  Here are each of the previously mentioned teams, with the starters listed along with their Draft Pick Value.  I’ve summed each at the bottom.  Click to expand.

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Here is the condensed version:

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So yes, the Seahawks appear to have done something remarkable, though perhaps not as remarkable as I expected.  Additionally, nearly all of Seattle’s contributors on defense were, in fact, drafted by the Seahawks, eliminating the possibility that they simply waited for late-round talent to prove itself in the league and then signed it.

The upshot:

There are a few possibilities here:

– The Seahawks are simply better at drafting then everyone else.  If you read the work I did on Skill vs. Luck in the draft, you know that’s almost definitely NOT the case.

– The Seahawks got lucky, and managed to string together several unlikely outcomes (very good players in the late round).  This one’s possible, and perhaps the most likely scenario.

– The Seahawks coaching staff is very good at turning its players into valuable contributors.  Also possible, but the level of results tells me to be skeptical here.

– Something else is going on….

We’ll need to explore these options in more depth to get a good sense of what’s actually happening.  For now, just know that what the Seahawks did, as far as roster-building goes, was EXTREMELY unlikely.  If we can figure out HOW they did it, it will tell us a lot about the kinds of strategies the Eagles should employ (even if it turns out Seattle did just get really lucky).

The Persistence of Sack Rate

Before we get to today’s topic, I need to clear something up about the last post.  It seems as though many readers came away with the wrong message. Nobody here ( falls into that camp (at least nobody who commented), but pulled the post from BGN and ran it on the front page of the site….

Hilarity ensured, at least if you read the comments.

So, let me make this clear:  I am a huge Nick Foles fan and the last post was not really bad news for him.  Yes, interception rate shows very little persistence from one year to the next, and that is, by itself, bad news for Foles (because he did so well this year and last).  However, I also mentioned that, (1) Foles rate was so good that even a relatively large amount of regression would still leave him with a very strong rate, and more importantly, (2) it looks as though some QBs are able to improve upon their interception rate over time.  That second part is a vital piece to this puzzle.  It means there is definitely skill involved in avoiding interceptions (hardly a surprise), but it also means that Foles may be able to actually improve his “true” ability level, which would obviously counteract some or all of the expected regression.

So, good news, not bad.

Now, for today, I decided to look at another aspect of Foles’ game thats drawn a lot of scrutiny: his sack rate.  

Foles has a career sack rate of 7.6%, and this season he was sacked on 8.1% of his drop-backs. (

The first question, obviously, is:  Is 8.1% bad?

Well, it’s not good.  This season, it left Foles ranked 27th in the league, just behind Kellen Clemens.  There were a few notable QBs who did worse though, like  Cam Newton (8.3%), Colin Kaepernick (8.6%), and Russell Wilson (9.8%).

I know what you’re saying, those are all “running” QBs, and their high sack rate should be balanced against the positives they bring in the running/scrambling game.  (If you weren’t saying that, you should have been).  While I’ll attack the positive/negative balance another time (check Football Outsiders’ advanced metrics for a very surprising look), allow me to posit another potential explanation:  they’re all relatively young.

Here is the list of QBs who finished with a worse sack rate than Nick Foles this year, along with their ages (right column).

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That’s a lot of 23 and 24.  This makes complete sense, for one of two reasons.  Either:

1) Sack avoidance is a skill that can be improved over time


2) QBs who take a lot of sacks don’t remains starters for very long.

The most likely explanation is that its a bit of both (as it usually is).  If a QB takes sacks at a very high rate, it’s going to be very difficult to be a productive offensive player.  There are exceptions, though, like the QBs I named above (Foles, Wilson, Kap, etc…).  Also, Ben Reothlisberger has a career sack rate of 8.2%.  Clearly, a high sack rate is not catastrophic.

For more, look at this year’s leaders:

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Jason Campbell, Jay Cutler, Sam Bradford, Matt Schaub, Matt Cassel….There are a lot go great QBs on that list, but also a handful of mediocre-bad ones as well.  Once again, sack rate isn’t everything.

Now, to the title of this post, persistence.

In my last post, we found that interception rate persists at a relatively weak level (at least within our admittedly limited sample).  That means one year’s rate has little informational value regarding the following season.

Let’s do the same thing with Sack Rate.  Simply put, does getting sacked at a high rate one season (like Foles this year) mean you’re relatively more likely to be sacked at a high rate the following season.

The answer, overwhelmingly, is YES.

Here is the chart:

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Again, the sample only consists of 100+ attempt seasons from: Eli Manning, Peyton Manning, Matt Schaub, Mike Vick, Matt Hasselbeck, Drew Brees, Tom Brady, Philip Rivers, Matt Stafford, Carsoln Palmer, Tony Romo, and Aaron Rodgers.  All told, that’s 112 qualifying seasons.  The same caveats I discussed last time apply here as well.

From the above data, the correlation value is 0.57, which is VERY strong compared to most statistics in football.

Clearly, a player’s style and skill have a large effect on their sack rate.  More importantly, Nick Foles is likely to be sacked at a high rate next year.  By itself, that’s bad news, but not as terrible as it might seem.

First off, the youth factor.  Here is a chart showing the average sack rate of the entire sample by qualifying season.  Note that these are NOT weighted numbers, so Hasselbeck’s 10.6% rookie rate counts the same as Aaron Rodgers’ 6%, regardless of the number of attempts.

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There is a clear and significant drop-off after the first season.  Of course, this year was Nick Foles’ SECOND season, but he did start just 6 games his rookie season, so I don’t think it’s unfair to look at this year as something like a continuation of his first season (though we can’t ignore the fact that a full offseason SHOULD play a big role).  There are definitely a lot of other factors in play here, for example maybe teams tend to improve the offensive line in the first offseason after anointing a new QB.  So nothing here is definite.

Still, from the sample I looked at, it’s certainly possible, and perhaps likely, that Nick Foles will see a decline in his sack rate next year.  However, the high correlation value suggests that we shouldn’t expect a significant difference.

I’m going to leave it there for now because I already feel like I’m rambling a bit, but let me give you one last chart and correlation value to think about.

How do interceptions and sacks relate?  The “narrative” frequently says that it’s “better” to take sacks than to throw interceptions.  Alone, that’s almost always the case.  But, it seems to suggest that one can and does take sacks INSTEAD of throwing interceptions.  For example, everyone that says Nick Foles doesn’t throw interceptions BECAUSE he’d rather take a sack is making a logical jump and assuming that the two outcomes are related.  I need to do A LOT more research on this, but preliminarily, here’s a chart showing the correlation between interception rate and sack rate, within our sample:

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A jumbled mess.  The correlation value is just 0.123 (roughly the same strength as the persistence of Int rate).  Remember, if the “Sacks INSTEAD of INTs” narrative holds, we should see a negative correlation (so more sacks equals fewer interceptions).  That’s not what we have.  As explained, I need more data and a deeper dig before coming up with any conclusion I can feel comfortable about.  In all likelihood, we need to groups QBs by “type” and evaluate them within discrete groups according to their attributes.

One more thing about Foles

Not a full post today, just a point I had wanted to include yesterday but forgot about.

The lack of excitement/”believers” regarding Foles may be a direct result of his “elite” skill.  as I said yesterday, it’s possible that interception-avoidance is Foles’ “plus” trait.  If that’s true, he’s never going to command a huge following.

Think about it.  The best plays Foles makes are, by definition, the ones you DON’T see, simply because they don’t happen.  As a fan (or anybody), it’s impossible to identify the plays in which a replacement-level QB would have thrown an interception but Foles does not.  Sure, we can talk about it in the abstract, for instance when he takes a sack and we say “it’s better than an INT”.  However, that’s obviously never going to be featured in a highlight reel.

In particular, Foles might be hurt by the way the game is analyzed today.  With the prevalence of All-22 breakdowns, countless people are going through game-tape and identifying everything that happened.  Once again, interceptions NOT thrown is never going to show up on those.  Instead, you’ll get a handful of wide open receivers that Foles missed.  The take-away, naturally, will be about what an “elite” QB WOULD have done, given the same openings.  However, that type of analysis doesn’t account for Foles’ “elite” skill.  Yes, maybe another QB would have made a few more plays.  However, he also may have then turned the ball over, completely negating the additional positive plays.

I’m going to try to dig a bit deeper into both interception rate and sack rate.  Hopefully, I’ll find evidence one way or another indicating the degree of skill involved in each.  Until then though, keep in mind:

IF Foles’ “elite” skill is his ability to NOT throw interceptions, he will never be fully appreciated.  Not only is it not a real “measurable” skill, but it doesn’t show up on replay.  While other QBs may be able to make a lot of positive plays that Foles can’t make, Foles may AVOID a lot of negative plays that those other QBs don’t.

That’s not as easily identifiable and it doesn’t lend itself to highlight reels, but in theory, there’s no reason it can’t be just as significant a skill.