By When NFL quarterback Jalen Hurts was ruled out for the season due to dangerous blood clots, fans of the Philadelphia Eagles were quick to write off the team’s chances.
It’s a common refrain among football fans: we could’ve been contenders if it weren’t for the injuries.
But the impact of injuries on NFL teams is a question that has never been fully quantified, says Joel Shapiro, a clinical associate professor of managerial economics and decision sciences at Kellogg.
“There’s a lot of very incomplete information out there about how much injuries matter,” says Shapiro. “How much, if at all, should teams care about whether a player is available to play or not?”
So Shapiro set out to create his own new metric that measures the cost of a player’s injury on their team. His metric, which he calls “Percent Cash Wasted,” takes an economic approach, calculating how much of a team’s payroll is sidelined due to injury each season.
When he applied the metric to over 350 NFL teams’ seasons from 2012 to 2022, he confirmed that injuries do make a difference to a team’s success. But the magnitude of that impact doesn’t match the common wisdom inside and outside football organizations.
“Losing payroll due to injury isn’t as big a deal as a lot of people would have thought,” says Shapiro. “But that’s with one probable exception: highly paid quarterbacks.”
Economics on the gridiron
Though the impact of injuries may seem like a matter for coaches and athletic trainers, Shapiro argues that it, like a lot of questions in sports, boils down to economics.
Teams have a finite amount of resources to spend in constructing their roster. In the NFL, that limit is defined by the salary cap, which governs how much each team can spend on its players each season.
“One of the most important things that any executive does, in sports or otherwise, is figure out how to allocate capital,” Shapiro says.
To find an edge in this system, organizations need to accurately value the different components of their team and distribute their budget accordingly. Invest in a top-tier offensive line, for example, and you may have less money to attract high-end linebackers.
And then there are injuries, the wild card that can throw the most-carefully laid roster strategy into chaos. In a contact sport like football, injuries are an expected part of the game; in Shapiro’s data sample, when you total up all seasons from all players, one out of three included at least one game missed due to injury.
Football analysts have tried to quantify the impact of these injuries on team performance through metrics such as Adjusted Games Lost or Wins Above Replacement-Adjusted Injuries Lost. Both of these approaches weigh injuries to starters and valuable players more heavily, acknowledging that losing a star quarterback is not the same as losing a third-string tight end.
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But Shapiro felt that an important piece was still missing from these stats: the cost, in dollars, of losing that player’s on-field performance.
“That’s what this study is all about, trying to understand how player injury affects decisions that teams should make around resource allocation,” Shapiro says. “I wanted to bring together the economic impact of injury and winning in a way that I hadn’t seen done before.”
Waste not, win more?
In an age of complex, AI-driven sports analysis, Shapiro’s Percent Cash Wasted metric sticks to basic math. It involves multiplying a player’s salary per game by the number of games missed due to injury, divided by the team’s total payroll.
For example, if a player is making $10 million a season and missed 30 percent of games, that’s $3 million wasted. At the current NFL salary cap of roughly $300 million, that’s 1 percent of a standard payroll lost. Tally up these figures across the roster and you get a team-wide figure for how much of its season’s payroll went to players unable to play.
In Shapiro’s data sample, teams’ Percent Cash Wasted ranged from as low as 1.1 percent to as high as 28.8 percent. On average, teams lost close to 10 percent of their payroll to injury each year—lower than many would predict, Shapiro says.
“You ask the public to guess, [and] they’ll say, ‘I don’t know, 30 percent?’” he says. “Even executives were guessing 15 percent to 20 percent.”
And as might be expected, less payroll lost to injury correlates with higher success—but only slightly higher. Winning a single extra game during the regular season aligned with roughly a 7 percentage point reduction in Percent Cash Wasted.
“In order to win one more game, an average team losing 10 percent of their payroll to injury would have to bring that all the way down to about 3 percent,” Shapiro says. “Which means that the depth that teams have gravitated to in this 11-year period that I looked at seems to be doing a pretty good job.”
In other words, the drop-off in quality from an injured starter to their backup isn’t hugely significant for a team’s success. But that rule has one big exception: star quarterbacks.
In Shapiro’s sample, there were five cases where a quarterback who cost more than 5 percent of a team’s total payroll was lost to a significant injury (Hurts’s salary is roughly 10 percent of the Eagles’ 2026 cap). In all five cases, those teams won far fewer games than their preseason expectations—and saw a deeper decline than would be expected if the same loss happened in any other position.
“All five teams completely tanked, which makes sense because of the importance of the quarterback to the team,” Shapiro says.
Better decision-making
In a post-Moneyball sports world where new stats arrive constantly, the best metrics are the ones that help teams make smarter decisions and get the edge on their competition, according to Shapiro.
“If your lever is money, and your goal is winning, and you want to spend money to win, then knowing the impact of injury absolutely can determine and should determine how you spend those dollars,” he says.
But front offices might draw opposing conclusions from Shapiro’s findings. Some might be more inclined to sign talented but injury-prone players, knowing that their time off the field won’t be as damaging as expected. Others might conclude that backups aren’t a significant drop-off in quality from starters and avoid giving big contracts to stars other than quarterbacks.
“Is talent really worth the premium that teams pay for it?” Shapiro asks. “I’m not sure which strategy is the right answer yet.”
In the meantime, Shapiro is interested in testing his Percent Cash Wasted metric in other sports, or maybe even in non-sports economic contexts.
“The resources that you spend on individuals who aren’t contributing is an interesting concept,” Shapiro says. “Lack of productivity and lack of availability are different things. But this notion of how efficient we are with our resources—that could be transferable to other settings.”
https://sports.yahoo.com/articles/cost-nfl-injury-172900589.html
