Is the Momentum Real? How Big Plays and their Psychological Effects work in NFL games

1. Intro

(Personal anecdote — feel free to skip)

I spent last week in New Orleans for the Week 16 Saints-Dolphins game. Admittedly, the timing was rough: 21 of 53 players on the Saints roster were on the COVID/Reserve list, and a rookie named Ian Cook was making his starting debut under center. Final score: 3-20. A blowout.

But I live in California, so meeting actual Saints fans in person was a first for me. The stadium energy was something else — I was riding high all the way to the fourth quarter.

The play that brought the house down:

Saints vs. Dolphins, Week 16 (December 2021) — a game-changing interception:

Second half, trailing by seven, and the Saints force a dramatic interception.

The momentum is here — tie game incoming! That's what I thought. The drive? One first down, then a quick three-and-out. "Maybe momentum really is just a myth," I muttered.

Still — put a great QB on the other end of that play, like Tom Brady, and you'd expect a huge gain on the very next snap. The gut feeling that points flow more easily after a turnover is hard to shake. And whenever a fourth-down gamble fails, the reaction is almost automatic: there goes the momentum. It comes up in every postgame broadcast, every fan argument online.

But is that intuition actually correct?

2. The Paper

Turns out someone took that question seriously enough to run the numbers.

In 2012, a team of researchers presented a paper at the MIT Sloan Sports Analytics Conference — one of the most prestigious academic venues in sports analytics — examining whether defensive big plays generate measurable momentum by boosting the success rate of the offense that follows.

3. What the Research Found

3.1. What Were They Measuring?

The study defined defensive big plays as six specific events:

1. Interceptions
2. Fumble recoveries
3. Stopping a fourth-down attempt
4. Safeties
5. Blocked field goals or punts
6. Muffed punts recovered by the kicking team

They then tracked the success of the offensive drive immediately following each event using three metrics:

1. Result of the first play
2. Whether the offense converted a first down
3. Whether the drive ended in a score

Sample size: 1,000 drives drawn from 2,921 games and 473,621 plays spanning 2000–2010. An equal number of "control" drives — following a TD, field goal, or punt with no preceding big play — were sampled for comparison.

The logic: if momentum is real, drives following big defensive plays should succeed at a measurably higher rate than the control group.

3.2. How They Filtered the Data

One obvious problem with this kind of study is that game situation distorts results. A team up 20 points with 90 seconds left doesn't need to score — so a drive ending in a kneel-down looks like "failure" even when momentum had nothing to do with it.

To control for this, the researchers restricted their sample to the first quarter with the score within 10 points.

They also ensured that starting field position was evenly distributed across 10-yard intervals (0–10, 10–20, all the way to the goal line), removing any field position bias.

3.3. The Result

Across all three metrics — first play, first-down conversion, and drive outcome — there was no statistically significant difference between post-big-play drives and the control group. (Full numbers starting on page 5 of the paper.)

First-down conversion rates differed by just 2 percentage points — well within noise. Drive outcomes — touchdowns, field goals, punts — were nearly identical across both groups. One small quirk: drives after safeties actually showed a slightly higher rate of allowing two points in return, but even that was within the margin of error.

4. Conclusions and Caveats

The paper's bottom line:

"Under the conditions examined, defensive big plays — including turnovers — do not measurably influence the outcome of the drive that follows."

That's not the same as saying momentum doesn't exist. The authors acknowledge the study's limitations openly and leave room for future research to find what this one couldn't:

1. Even if a handful of defensive players get fired up after a big play, the team-level metric used here — drive success rate — may be too broad to capture individual psychological effects.
2. Position-specific or player-level analysis, particularly at QB, might tell a very different story.
3. A fired-up defense may simultaneously inspire the opposing offense, with the two effects canceling each other out at the aggregate level.

The paper's final sentence captures the situation cleanly:

Even with this evidence, the debate between fans, players, coaches, writers, and analysts about the presence and effects of psychological momentum in the NFL will likely continue for the foreseeable future.

As someone who writes academic papers for a living — that's a well-crafted closing line.

5. My Take

The methodology is solid, and I came away genuinely impressed. That said, I've always felt momentum matters more in late-game situations, when the emotional stakes are highest. Studying only first-quarter data? The psychological effect, if it exists, would naturally be dulled — though I understand why the fourth quarter is impossible to control for cleanly.

The player-by-player angle feels like the most promising direction for future work. Brady's reputation for immediately converting turnovers into scores is legendary. Mahomes — the way he ruthlessly pounced on Houston's collapse in that playoff run — is cut from the same cloth.

Personally, I still believe in momentum — just not as something that materializes automatically after a big play. The way I see it, certain players and coaches are simply wired to exploit the opening a turnover creates. The big play is just a door. Whether anyone on offense is built to walk through it is a separate question entirely. That framing, incidentally, fits perfectly with what this paper found.

6. A Side Note (Patriots Fans, You've Been Warned)

MIT, the home institution of the paper's authors, sits in Boston — Patriots country. And near the end of the paper, there's a sentence that has exactly the energy you'd expect:

The players on offense also had nothing to do with the prior big defensive play; they were on the sideline when it happened (the exception is utility players like Patriots wide receiver/defensive back Julian Edlemen).

The Edelman reference serves essentially no purpose for the paper's argument. The authors just… found a way to work in a Patriots shoutout. Classic. Also — and this feels relevant — they misspelled Edelman. Twice.

7. Closing

Diving into this research made it clear just how many people are doing serious academic work on the NFL. There's a whole ecosystem of this stuff, and I plan to keep covering it. Thanks for reading.