UDFAs Have Real Impact

The Chicago Bears are currently undergoing a major period of roster churn, and at the “bottom” of that churn is a mass of undrafted free agents. I imagine that many Bears fans have seen the claim that as much as 30% of NFL rosters are composed of undrafted free agents, but that perhaps like me those fans have been a little skeptical. Frequently, this factoid is meant with the cautionary note that of course desperate teams need UDFAs to fill their ranks, but that good teams are built in other ways. To put it another way, even with UDFAs on some rosters, it’s easy to dismiss their contributions.

It’s also probably wrong to do so.

I was curious about what roster composition looks like for a good football team, and because I had a few free minutes I decided to do a dive into actual numbers instead of my own personal guesswork and beliefs. This is not intended as a definitive study, but rather a simple check against actual rosters to see if conventional wisdom had a basis in reality. I came up with a very simple cutoff for recent “good” teams–I wanted teams that went to back-to-back playoffs in 2020 and 2021. This gave me seven teams, with four from the AFC (the Bills, Chiefs, Steelers, and Titans) and three from the NFC (the Rams, Bucs, and Packers). I then pulled their rosters from Pro Football Reference for the start of that run (2020) and went to work on figuring out their composition in terms of how players arrived on the teams in question and put together a few observations.

The impact of UDFAs is real.

Based on my sample, it is likely true that across the entire NFL roughly 30% of the names on rosters were not drafted when they began their NFL careers, because that number is close to what I found. This is not simply a case of bad teams being desperate to fill their rosters with bodies, either. Instead, 33% of the 475 names on these rosters–158 players in all–were undrafted free agents at one point. Admittedly, only 114 of these players (24%) were actually UDFAs within the first three years of their contracts or still playing without entering general free agency. Another 9% of the rosters were established players who had been signed just like any other free agents would have been. However, that only underscores the fact that those UDFAs went on to earn additional contracts, and that a third of the players on teams heading into back-to-back playoff runs were never drafted.

To be fair to skeptics, UDFAs are not equal contributors to first- or second-rounders. Mixing both groups together (UDFAs and Free Agents with UDFA origins) sees only 318 of a total 2462 starts (13%) come from UDFAs. To put that into a simpler context, though, these teams collectively only found 364 starts from the players they drafted after the third round. The third day of the draft barely out-performed the UDFAs. Moreover, in terms of total games played, UDFAs offered 1453 games out of 5192 (28%). It’s not just names on a roster, then, and it’s not just on bad rosters.

In short, even playoff teams filled their ranks with undrafted free agents, and it is almost impossible to dismiss their contributions as limited to teams that aren’t ready to compete. Contending teams have a solid UDFA presence.