When the Patriots placed N'Keal Harry on injured reserve and re-signed Demaryius Thomas, the league's oldest roster got a little bit older. 

By exchanging the 21-year-old rookie wideout for the 31-year-old veteran, the average age of the Patriots roster bumped up from a league-high 27.0 years old to 27.2. 

According to Jimmy Kempski of the Philly Voice, who compiled average ages of all NFL rosters once teams were cut down to 53 players on Saturday, the Patriots had the oldest roster in football for the first time in the last five years. In 2018, the average age of a player on Bill Belichick's initial 53-man roster was 26.8 years old (30th in the NFL). In 2017, they were at 26.5 (26th). In 2016 and 2015 they were right around the league average at 26.1 (15th) and 25.0 (13th), respectively.

You might be saying to yourself, "Well, yeah. They have the oldest quarterback in football. By a wide margin. Of course they're near the top of the list." 

That's true. At 42 years old, Tom Brady skews New England's average age to a certain extent. But even if the Patriots replaced Brady with a much younger player closer to the league average -- let's say, 26 years old -- they'd still have the oldest roster in football with an average age of 26.8. That'd be slightly ahead of the Eagles and their average age of 26.6. 


What's fascinating about how the Patriots roster breaks down is that even with Brady leading the offense for another year, it's the Patriots defense that is the older of the two units. It's close, but the defensive players on the roster have an average age of 27.0 while the offense averages 26.9. 

If you break it down by projected starters, the Patriots defense is still older than the offense. 

With a "sub" unit -- which plays more snaps than "base" in this day and age -- of Devin and Jason McCourty, Stephon Gilmore, Patrick Chung, Jonathan Jones in the secondary, Dont'a Hightower, Ja'Whaun Bentley, Kyle Van Noy, Jamie Collins, Lawrence Guy and Michael Bennett, the average age is 29.1. 

Offensively, Brady, Julian Edelman, Josh Gordon, Demaryius Thomas, Sony Michel, Ryan Izzo, Isaiah Wynn, Joe Thuney, Ted Karras, Shaq Mason and Marcus Cannon have an average age of 28.5.

Taking all those numbers into account, the conclusion is the same: In NFL terms, the Patriots are old. 

Of course they're not oblivious to that fact. They drafted in bulk over the last two years -- selecting 19 players in 2018 and 2019 -- with the hopes of infusing the roster with young talent that could help the Patriots sustain their two-decade run of success. They currently have 14 first and second-year players who make up slightly more than a quarter of their active roster. 

The advantages of getting younger are obvious. But there is a benefit to having an experienced 53-man group. The Patriots are loaded with players, particularly on the defensive side, who can adjust on the fly. From week to week -- and from snap to snap -- the Patriots defense proved in 2018 that they could alter their pass-rush plans and coverages to confuse opposing quarterbacks and play-callers. Operating that way might've proven difficult for a roster made up of players on rookie deals.

There may be another benefit to being older -- aside from on-the-field experience and football IQ -- that the Patriots and others have tapped into.

Interestingly, the last four Super Bowl champions were all inside the top-10 in terms of oldest teams in the league, according to Football Outsiders "snap-weighted age" metric. (With that measurement, Football Outsiders doesn't just average out the ages of NFL rosters. They take into account who's playing and how much.) 

The Patriots were the oldest team in the NFL according to SWA last year (27.9 years old). Eagles were seventh in 2017. Patriots were 10th in 2016. Broncos were seventh in 2015. Meanwhile, three of the last four Super Bowl losers were also inside the top-10 in SWA. The only team that wasn't (the Rams last year) were 11th.


How can that be explained? There appears to be a bit of a roster-building market inefficiency that teams can exploit if they're willing to watch the average age of their team climb. 

The rookie wage scale, introduced by the current collective bargaining agreement, has generally steered the NFL away from mid-tier veterans. Older stars still get paid if they can perform up to expectations. But mid-tier vets have found themselves out of the league more and more frequently in recent years because rookie contracts are cheaper and teams feel as though they can get similar production from younger options. 

The Patriots and other older clubs -- it's probably no coincidence the Eagles, widely considered one of the smartest front offices in football, have the second-oldest roster in football -- have shown a willingness to turn to mid-tier (in terms of salary) veterans like Edelman, Van Noy, James White, Matthew Slater and Duron Harmon into critical pieces. They're more expensive than rookies, but the return on investment from those players has been massive. 

Of course, on the one hand, maintaining one of the oldest rosters in the league can be a dicey proposition. Older players tend to get hurt. Older players tend to see their levels of performance drop quickly. 

On the other, the last four Super Bowls would tell you that stockpiling capable veterans isn't a terrible idea. In 2019, the Patriots will hope that trend continues because theirs is the oldest roster in football.

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