Are Teams Faking Injuries? Part I

Are Teams Faking Injuries? Part I
Are Teams Faking Injuries? Part I
Photo: USA Today Sports Images

Guest Column by Jared Cohen

Conservatively, I would estimate there were about 500,000 words dedicated to NFL gamesmanship over the few months. But in all the talk about deflated balls and illegal substitutions during the 2014 playoffs, one area has remained relatively unexamined.

With an increase in fast-tempo offenses, are defenses faking injuries in an attempt to slow them down?

As a Philadelphia fan, I'm predisposed to assume there are massive conspiracies against the Eagles. So since the Eagles started running Chip Kelly's offense, my eyebrow has gone up every time an opposing defender needed an injury timeout.

The Eagles' high tempo is a part of their strategy, and one that opposing teams would love to minimize, particularly if they aren't well prepared for it. Faking an injury can mitigate a high-tempo offense, given there's no cost to the injured team outside of a timeout in the last two minutes of a half and the requirement that the injured player must sit out the next play.

This might become an even more important question after the new rule passed by NFL owners today, which will allow an athletic trainer spotter in the press box to call a timeout to pull a potential injured player out of the game. Calling injury timeouts will no longer be limited to the officials on the field, which means we are likely to see more of them.

Could teams really be faking injuries? It's an idea that's hard to critically evaluate, but using play-by-play records, we can start to see if any suspicious patterns emerge.

Data Collection and Methodology

I examined play-by-play data from all the 2014 regular-season games, and identified all the in-game injuries noted in the play descriptions. In case you haven’t read play-by-play before, each play has its own line and explanation, and any play that resulted in an injury timeout is noted. Below is an example:

2-10-DET 40 (14:05) (Shotgun) 10-E.Manning pass incomplete deep middle to 80-V.Cruz (27-G.Quin). DET-27-G.Quin was injured during the play.

If an injury was noted as a stoppage, I marked if it was suffered by the offense, defense, or special teams. There were approximately 700 total observations. (Today's article only discusses these 2014 plays; a second article later this week will discuss play-by-play data going back to 2010.)

After gathering the data, one additional adjustment required is for play frequency. The more snaps a player gets, the more likely he is to sustain an injury. Therefore, any team that runs more plays is probably going to see a higher absolute number of injuries. To account for this, I also looked up the total number of plays for each team's offense and defense during the course of the year, to understand the rate of injury rather than just total numbers.


There were 692 injuries in the play-by-play data, 66 of which were special-teams plays and so were excluded (faking these wouldn't slow down an opposing offense). Looking at the rate of defensive injuries against (adjusted for number of plays), we can see which teams are seeing the highest rate of injury among their opponents -- and are potential victims of fake injuries.

When we look at it on a rate basis (number of injuries divided by number of total offensive plays), the Eagles are second in the league and roughly 50 percent above the league average.

But before we get any further down the faking rabbit hole, what if there's a simpler explanation that doesn't involve fake injuries? There's another obvious possibility to explain why the Eagles are so high in defensive injuries against. What about the idea that as you run more plays, players get more physically exhausted, and therefore are naturally more susceptible to injury?

To test this, I took a simple look at whether injury frequency varies by quarter. If teams get physically tired during the course of the game and that leads to more fatigue and more injury, there should be more injuries as the game goes on.

In absolute terms, the number of injures does rise dramatically as the game goes on. Injury stoppages in the fourth quarter occur at double the rate they do in the first quarter. Part of that can be explained by the fact that the clock stops more frequently in the fourth quarter than it does earlier in the game (and thus there are more plays), but that wouldn't explain a two-times difference.

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What you've also likely noticed is that the increase is much more pronounced on the defensive side of the ball than on offense or special teams. We'll come back to that later.

For the time being, let's move on to looking for evidence of fake injuries. This time I looked for relationships between injury frequency and number of plays in specific situations.

As a general framework, I split the types of injury stoppages into four buckets:

1. While on offense, your own team suffers an injury (Own-Offense)
2. While on defense, your own team suffers an injury (Own-Defense)
3. While on defense, your opponent suffers an injury (Opponent-Offense)
4. While on offense, your opponent suffers an injury (Opponent-Defense)

We saw that overall injuries increase as the game goes on, but it seems much more prevalent on the defense, which is the side that would be interested in faking injuries. So can we look a bit deeper to see if play frequency increases injury risk across each type of injury stoppage? The idea that running more plays increases the rate of injury should not be exclusive to offense or defense, although it appears that way at first glance; it's hard for me to believe that defensive players are in any worse shape or take any harder hits than offensive players.

To take a look at the issue, I ran some basic correlations across each of those four injury types, looking at the number of plays run and the rate of injury. Just to clarify, I summarized the four below:

1. The offense runs more plays and gets injured more often (this would be a good offense)
2. The defense runs more plays and gets injured more often (this would be a bad defense)
3. The defense runs more plays and your opponent's offense gets injured more often
4. The offense runs more plays and your opponent's defense gets injured more often

Again, if the rate of injury increases with more plays, we should see relationships in each of these situations. So what do we see?

1. On the offensive side of the ball, there's actually a relatively weak negative correlation between running lots of offensive plays and suffering offensive injuries. If you want to believe in things like Chip Kelly's Sport Science program, you would expect a negative relationship as teams that employ high-tempo offenses should be more adequately prepared to stay healthy in those schemes. While a very slight negative relationship exists, it doesn't look to be that large, if it even exists at all.

2. Earlier we saw defenses suffering more injuries as the game goes on ... and yet, when we look at number of defensive plays per game and the rate of defensive injury, there really doesn't seem to be any relationship. Teams with defenses that are on the field a lot don't seem to get injured at a higher rate than those who execute fewer plays.

3. Our next picture shows a similar lack of correlation, this time between defensive plays per game and the rate of opponent offensive injury. This idea would be that if an opposing defense is really bad, your offense gets more plays, and might get hurt more frequently. But the data shows nothing that looks like a relationship.

4. Now it's officially interesting. When we look at the rate of defensive injury against offensive plays per game, there is our most significant positive relationship. A correlation of 0.39 is way more than we have seen in the other three situations, and it's also the only one where there is a clear incentive to fake injuries.

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Taken in isolation, you could argue the fatigue theory. But it's tougher to make that argument when you don't see anywhere close to the same relationship in all other situations. The only players who show a substantial increase in injury stoppages as number of plays increase are opposing defenses.

To me, that's pretty suspicious. Either opposing defenses are the only ones who suffer from fatigue-related injuries, or maybe some of the injuries aren't injuries at all.

But is this a pattern over time? Or just statistical happenstance in 2014? Later this week, part II of this article will examine the last five years to see if this is a consistent pattern, as well as what else we can observe about injury stoppages.

Bonus: The Jevon Kearse All-Stars

One last thing I did with this data, after pulling it together, was dig through and sum up all the specific players who sustained injuries in a game this season.

I wanted to look into it because I was really interested in what I’ve termed the "Jevon Kearse All-Stars." It may just be a bad memory on my part, but one of the things I really remember about Jevon Kearse’s tenure with the Eagles was his tendency to hurt himself and fall to the ground like he got shot. I feel like his injuries always looked more serious than they actually were. It’s possible I’m misremembering, and if so I apologize to the Freak. But with that said, here were the leaders in injury stoppages in the NFL this year:

  • Jonathan Goodwin, NO (5)
  • Vontaze Burfict, CIN (4)
  • Ryan Clark, WAS (4)
  • Marcus Gilchrist, SD (4)
  • James Ihedigbo, DET (4)
  • Johnathan Joseph, HOU (4)
  • Jason Pierre-Paul, NYG (4)
  • Rodger Saffold, STL (4)

Now I’m not accusing these guys of faking injuries; these just happened to be the guys with the most injury stoppages in the play-by-play data (excluding special teams, which most of these guys don’t play anyway). Jonathan Goodwin: your Golden Ace Bandage Trophy is in the mail.

Jared Cohen is a contributor to and the author of the book How I Got on Jeopardy … and Won. He can be reached on Twitter @jaredscohen. If you have an idea for new research or an interesting take on a football subject, you can send your guest column idea to us at Contact Us


24 comments, Last at 08 Apr 2015, 8:50am

#1 by johonny // Mar 24, 2015 - 4:24pm

If you want to double check go do the same analysis on the era of the Jim Kelly K-Gun offense where we know teams were faking injuries to slow them down. They made rule changes to try to prevent teams from doing it back then.

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#13 by Aaron Schatz // Mar 25, 2015 - 12:04pm

PBP was not standardized to the same extent; therefore all injury timeouts were not necessarily listed in the PBP at the time.

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#2 by Led // Mar 24, 2015 - 4:40pm

Here's my solution to faked injuries. The rule making it a penalty if more than 11 men are on the field, regardless of whether they are actually taking part in the play, is a relic from a bygone era when offenses huddled between every play (and, frankly, when teams substituted less). The rules did not anticipate offenses using tempo to prevent the team on defense from putting the personnel it wanted into the game. Now that offenses have made the game more fluid, the defensive substitution rule should be changed. If hockey teams can change shifts on the fly, there is no reason the NFL can't have a rule permitting substitutions where guys are leaving the field, totally uninvolved with the play, at the time the ball is snapped. So no more free five yard penalties when Manning or Brady snap the ball when the NT is a yard from the sideline. But any interference at all by a 12th or 13th (or 14th, etc.) player would be a 15-yard unsportsmanlike conduct/illegal participation penalty.

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#16 by Noahrk // Mar 26, 2015 - 11:15am

Good suggestion. It reminds me of the offsides rule in soccer, it doesn't get applied unless the player who is offsides participates in the play. I wouldn't do it a 15-yard penalty, however, just the usual 5, as chances are it will be inadvertent, as it sometimes happens.

Who, me?

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#24 by armchair journ… // Apr 08, 2015 - 8:50am

You've got my vote..

Though on second thought, I could see this being tough on a defense, constantly having to watch out for the ol' Randy Moss "pretend to be subbing out but line up wide just before the ball is snapped." Might be a bit of a headache to referee.

Edit: I see this discussion jumped to a lower thread, already.


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#3 by Sporran // Mar 24, 2015 - 5:14pm

It's possible that Defense is more physically demanding than Offense, and therefore we would expect more injuries on Defense regardless.

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#17 by Noahrk // Mar 26, 2015 - 11:17am

I'd argue the opposite, with RBs, QBs and WRs getting the hardest hits, and WRs and QBs being the skinniest guys on the field along with CBs.

Who, me?

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#18 by chemical burn // Mar 26, 2015 - 12:14pm

Yeah, but they are hit much more infrequently than o-line, d-line and LB's, who suffer an impact on nearly every play. WR's and QB's can go a whole game without really getting touched whereas a 250 pound MLB/ILB likely has a 300 pound guard slamming into him at full speed a dozen or more times a game. I think the cumulative impact a DE or DT suffers is probably the greatest of any position in the game...

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#5 by joel.schopp // Mar 24, 2015 - 7:07pm

One way to test is to test if there is a higher rate of injured players returning to the game or injured players returning the following week for defenses playing higher tempo offenses. If the player is out the rest of the game and/or the following week it is much more likely a legitimate injury.

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#7 by chemical burn // Mar 24, 2015 - 9:40pm

Yeah, I'm not sure if the data exists in a way that's easy to explore, but the Eagles definitely suffered from a notable amount of "players goes down, leaves field of play for a single play and returns immediately." I would also say you could look at if injuries are occurring at a higher rate during successful drives - that is, teams would try to slow down the Eagles only when their fast pace was succeeding. No one is going down during a 3 or 4 and out.

These are the two ways in which I as a fan felt aware of the defense trying to slow down the Eagles - a longer drive hits the redzone, Antrel Rolle goes down and out of the game for a single play so the defense can switch in a different personnel group.

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#6 by PaddyPat // Mar 24, 2015 - 8:10pm

Given the relatively small sample, I would wonder if statistical outliers getting repeatedly injured in the fourth quarter, along the lines of your "All-Stars" plays a role. Ihedigbo, for example, as far as I can recall from the year he spent on the Patriots, was a player who would repeatedly suffer stingers in the fourth quarter. That might still be on-going for him. Obviously, this doesn't explain the curious defensive correlation that your data has uncovered, but I would be curious to see the statistical power of the finding, eg. how likely is the correlation to be the result of chance.

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#8 by MJK // Mar 24, 2015 - 10:31pm

Well, if you consider "being completely gassed" to be a minor injury, then defenses facing up tempo offenses late in he game maybe are facing real injuries.

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#9 by BaronFoobarstein // Mar 25, 2015 - 12:14am

Suppose that a player is hurt and is unsure whether he is injured. Call the time until he has determined whether he is injured the doubt. If a play is imminent when a player is still in doubt he is likely to select himself as injured. That's not faking, it's a natural result of less recovery time between plays.

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#10 by nat // Mar 25, 2015 - 10:44am

Interesting work, nicely presented.

Have you considered how injuries could cause the number of plays to change, instead of the other way around?

If my opponent's defense suffers a lot of injuries, my offense will be able to extend drives more easily. Over a season, if I'm lucky enough (or dirty enough, or simply just putting enough stress on opposing defenses) to face a lot of injured defenses, I'm likely to get more offensive plays than usual.

If my own offense is injury-prone, I will end up with fewer offensive plays, too.

I have no idea how big this effect could be. But I suspect it's there to some extent. It it would explain your #4 case having the highest correlation.

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#11 by LondonMonarch // Mar 25, 2015 - 10:49am

But how does the QB (or the officials) know which of the players will be participating when the ball is snapped?

Won't this lead to a "13 angry men" formation where Belichick has 13 players milling around, and 2 will just sit down as soon as the ball is snapped - but until then the QB has no idea?

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#12 by Led // Mar 25, 2015 - 11:09am

I'm guessing this was a response to my comment above. My answer is it wouldn't be an issue (like it's not an issue in hockey) because if a guy isn't attempting to leave the field when the ball is snapped, he would be deemed to be participating and it's a penalty.

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#19 by chemical burn // Mar 26, 2015 - 12:21pm

Come on - Belichick would definitely play games with this. Rex Ryan, too, who already runs "formation-less" defenses when facing Brady and Manning. Allow them an extra 3 guys to milling around outside the numbers and "be headed towards the sidelines" and they'd find a way to exploit it.

For example, if 4 player jogs towards the sidelines and only 2 actually exit the field of play, is that a penalty? Can't they argue they're just headed to their spots at CB or S? It would definitely be used for deception.

Right now, football doesn't have an over-abundance of rules with clear, tight parameters - why get rid of the few ones they do have? Why insert more judgement calls into a game that has too many already? The sport is so different from hockey that making the comparison doesn't make sense - hockey has far fewer stoppages whereas a football game consists almost entirely of pre/post-play stoppage time. There's also a wildly different number of players on the field and football has many more rules governing which players can do what (see the Patriots/Rans playoff game.) Don't take something clear and make it unclear.

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#20 by jtr // Mar 26, 2015 - 1:16pm

The Rex mention is particularly apt considering that Buddy had a 14-man goal line package drawn up in his playbooks ( In certain situations where half-the-distance isn't a real punishment, you might have 14 players mill around as if 3 would sub out at the last second, only to actually run a 14 man defense. You burn time off the clock and force your opponent to waste a goal line play, and maybe you get a good hit on the QB while you're at it. And nothing says Rex Ryan like a formation with 6 DLs and 7 LBs!

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#21 by mehllageman56 // Mar 26, 2015 - 2:34pm

I would have loved to have seen that. The other big shenanigan a team could do with a substitution rule like hockey's, would be to hold a player in reserve. Two guys run off, one comes in, but when the other team's quarterback rolls out toward your sideline, the eleventh player runs onto the field to deck the quarterback immediately. Or, when a team looks to get a breakaway run or pass, the eleventh player jumps onto the field right before the goal line to make a saving tackle.

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#23 by Led // Mar 27, 2015 - 3:51pm

Why would you have to let teams be able to send guys out on the field after the play started? One doesn't follow from the other. This and the concerns expressed above are VASTLY overstated. It's not worth putting your defense in a vulnerable position and risking a 15 yard penalty to try play mind games.

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#14 by jtr // Mar 25, 2015 - 11:00pm

The Giants have been notorious for faking injuries under Perry Fewell (including two players at once a couple times). Plus, the Giants have had a huge amount of real injuries in recent years, so the Eagles 2 games each year against Big Blue might be driving their totals up a little bit.

The Kearse All Stars list is interesting. JPP has definitely earned a reputation as a drama queen; he quite often looks down for the count only to return on the next series. I suppose he has less of that act-tough-at-all-costs attitude than other players. Ryan Clark has played like a cruise missile his entire career and I don't doubt that he fully earned it every time he couldn't get up on his own. I haven't watched too much of Burfict, but usually UFA LBs crack the lineup by playing with reckless abandon and being willing to sacrifice their bodies; James Harrison and Bart Scott come to mind. Burfict's dirty play probably doesn't help, as I'm sure an opposing player never misses a chance to take a shot at him. I don't really know anything about the rest of these guys--do any of them actually seem to be fakers?

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#15 by bubqr // Mar 26, 2015 - 8:03am

Really interesting study – Have you planned to study the timing of those injuries (ie more likely to happen after X first downs than earlier in the drive)?

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#22 by OSS117 // Mar 27, 2015 - 9:00am

More than half the league by now is using that Catapult system for training, practice, and monitoring injuries. I don't know if any of those findings/data are available, but it should be able to shed light on which side of the ball plays with more exertion, intensity, etc. And whether/how that might make them more vulnerable/susceptible to injury. Eagles are one team that uses it. Tho I don't know if they're used in actual games or just practice. Probably not since it might open them to liability. Idk, but it would be interesting to see the data.

Not all injuries are documented in gamebooks. Iirc, just the ones that result in a stoppage. Which is all you want anyways if looking specifically at faking injury. But if you're looking at who is prone to attrition and the effects of a higher volume/rate of plays, I'd think those should somehow be accounted for.

I would guess most of these are cramp related. Often you see guys just limp off between downs. But high tempo teams don't allow that chance, and players are likely prepped in advance to just go down and wait for the ref to stop it than try to hobble off.

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