Today I’m following up on yesterday’s post. I encourage anyone who hasn’t done so to read that before moving to this post.
Now, onto the important stuff.
I discussed how we can apply Game Theory to NFL 3rd Down Strategy, highlighting what appeared to be a large inefficiency in 3rd down play-calling. Basically, we should expect the Run/Pass play call breakdown to reach a point at which both options are equally likely to succeed.
This is the point of equilibrium.
I did some more digging into the numbers, the result of which is better resolution and more actionable intelligence. Yesterday we looked at all plays run on 3rd down with between 1 and 5 yards to go.
Given what we know about the NFL, this is a very wide range for yardage; teams should run more often on 3rd and 1 than on 3rd and 5. Below, I’ve broken the data down into smaller parts. The results are encouraging. Here is the complete table. Note that I’ve put this together under the assumption that the original ranges are inclusive of each smaller range (3rd and 1-5 INCLUDES the 3rd and 1 stats), if that’s not the case, then this data is useless.
See why I find it encouraging?
Starting with the bottom row (3-5 yards), we see that the NFL has, in fact, reached the expected equilibrium (close enough). In a 3rd down situation with between 3 and 5 yards to gain, run and pass plays are both equally likely to succeed.
Remember the Tecmo Bowl Model, though. As we can see, the equilibrium point occurs at a Run/Pass split that his HEAVILY tilted towards the Pass (18%/82%). This is expected. The important part is that play-callers appear to be operating efficiently, that is, calling runs and passes with the theoretically correct frequency.
This could be a coincidence, but given that we made the prediction beforehand and its the logical extension of yesterday’s theory, that seems unlikely.
Now the important part:
While the league looks to have hit its Nash Equilibrium in 3rd and 3-5 yard situations, it DOES NOT look to be operating efficiently in 3rd and 1 and 3rd and 2 situations.
Again, our theory is that at the league level (a very important point), the call rate on 3rd downs should naturally evolve to a point at which the average success of both run and pass are close to equal.
Given the information above, teams should be running a lot more often on 3rd and 1. Even though they are already calling a run roughly 75% of the time, the success rate of such plays is still significantly higher than for pass plays.
So….teams should run more, which will cause defenses to adjust by “expecting” the run more (Tecmo Bowl), which will presumably lead to Pass plays being “less expected” and therefore succeeding a higher percentage of the time. Over time, the success rates for both run and pass should converge until they reach equilibrium.
Looking at the 3rd and 2 situations, we can still see some inefficiency, though it’s not as severe as in the 3rd and 1 situations. Again, the process should be the same. Offenses should run more, defenses should then commit to the run more often, and pass success rates should increase (while rush success decreases) until both Run and Pass have an equal chance of success.
It’s very important to note that this is League-level data. Therefore, applying it to any individual team is tricky. We can NOT say, for example, that the Eagles should definitely run more than 75% of the time in 3rd and 1 situations. All we can say is that the LEAGUE should run more than 75% of the time in these situations. It’s certainly a logical step to then take it to the team level; but know that it becomes more difficult at that point, since you have to weigh individual strengths and weaknesses as well as the relative strength of the opponent.
Conclusion:
– NFL offenses are not running enough in 3rd and 1 and 3rd and 2 situations.
– This is a short-term opportunity to exploit an inefficiency in the game. Once offenses adjust, defenses will too, with the end result of equal success rates and no advantage.
– While I didn’t discuss it here, teams should likely ALSO be running more often in 3rd and 3-5 yards situations, though for a different reason. I haven’t run the numbers yet, but my guess is that once we incorporate 4th down opportunities into the equation (especially 4th and 1), running will still carry the higher overall success rate (and therefore need to be used more until the defense adjusts).
– This, along with 4th down strategy that we previously discussed (see tab on menu bar), is an area ripe for a “forward-thinking” coach to take advantage of.

