Adrian Peterson was already focused on the 2012 season after tearing his ACL against Washington on Christmas Eve 2011. With Week 1 of 2012 on his mind, he opted for early surgery with Dr. James Andrews, according to Sports Illustrated. Hours after the procedure, Andrews told Peterson that the running back may not be able to raise his leg while sitting for a couple of weeks. Peterson raised his leg right then and there.

Peterson’s on-field career has been defined by defying expectations. As a rookie, he broke the single-game rushing record and finished second in the league in rushing yards. He changed how we view both torn-ACL-recovery timelines and post-ACL-tear performances after his late-2011 injury. Now, in 2018, he’s challenging expectations once again, but now it’s about his matchup with Father Time.

Peterson was signed off of the NFL’s scrap heap in August after Washington rookie running back Derrius Guice tore his ACL in a preseason game, and Peterson has been everything Washington needed from its lead back. At 33 years old, the future Hall of Famer has carried the ball 127 times for 587 rushing yards (4.6 yards per attempt) and four touchdowns, and he’s added 151 receiving yards and a touchdown on nine catches. His yards per attempt are better than those of his 2015 season when he led the league in rushing yards, attempts, and touchdowns while earning first-team All-Pro in his final healthy season in Minnesota. He is currently averaging 5.4 yards per touch, the third-highest mark of his career after his rookie year and his MVP season. He’s sixth in the league in rushing yards per game (83.9) and in yards per attempt among backs who have more than 100 carries this season. The players ahead of him on both of those leaderboards—Joe Mixon, Todd Gurley, James Conner, and Ezekiel Elliott—are all between 22 and 24 years old (or young enough to have been middle-schoolers when Peterson was drafted seventh overall in 2007), and some of the best young backs in the league say they idolize his comeback season.

This isn’t supposed to happen at the running back position, and there’s little precedent for backs in an age-33-or-later season to be putting up these numbers. Let’s start with his workload. Peterson has already rushed the ball 127 times and touched the ball 136 times this year. Only 23 other running backs his age or older have touched the ball that many times in an entire season. Peterson has done it in seven games. At Peterson’s current pace of 311 touches, the only running backs 33 or older who will have touched the ball more than him in a season are Pittsburgh’s Franco Harris (the guy from the Immaculate Reception) and Washington legend John Riggins. Peterson is getting the ball more than just about any old running back ever, but he’s also doing more with it. Only 10 other running backs 33 or older have ever averaged more than 50 rushing yards per game (minimum seven games). Peterson is averaging 83.9, second only to (Washington fans rejoice) Riggins.

Workload and total yardage aside, Peterson’s efficiency is also historic. Here’s the list of players 33 or older who have averaged more than 4.5 yards per carry (minimum 100 rushing attempts):

1961: Hugh McElhenny, Minnesota Vikings

1962: John Henry Johnson, Pittsburgh Steelers

2018: Adrian Peterson, Washington Redskins

Even if we lower the number to 4.0 yards per carry, we add just four players: Marcus Allen, Ricky Williams, Warrick Dunn, and Joe Perry. Peterson is having among the most prolific and the most efficient rushing seasons ever for an old running back.

It’s quite the reversal of every trend at the position right now. After Peterson signed his six-year deal for $36 million guaranteed in 2011, the running back position has trended toward younger and cheaper players while middle-class free agents have been priced out and backs older than 30 have mostly disappeared altogether. (The exception to this is Frank Gore, who at 35 is one of the oldest players left in the league and has put together a Hall of Fame case based largely on longevity.) Now Peterson is proving that older running backs are not only worth pulling out of the free agency abyss, but that they can also contribute right alongside the NFL’s youngest, shiniest backs.

Resetting expectations is not new for Peterson. His college highlight reel is among the best we’ve seen. As a 22-year-old first-year pro at a time before teams expected rookie backs to be their primary back, he finished second in the league in rushing yards and ran for 296 yards on just 30 carries in a game against the Chargers.

In 2012, Peterson returned to the field nine months after his ACL tear and finished 8 yards shy of tying Eric Dickerson’s single-season rushing record and was named MVP—an award no other running back had won since LaDainian Tomlinson in 2006 and none have won since.

Of course, perhaps more than his record-setting 2012, Peterson’s late career may be remembered for his 2014 arrest after injuring his son’s back, ankles, buttocks, legs, and scrotum while disciplining the 4-year-old with a tree branch. Peterson was charged with felony child abuse and ultimately took a plea bargain that reduced the charges to one count of reckless assault, a misdemeanor, in November 2014. Two weeks after the deal was reached, Peterson was suspended without pay by the league for the rest of the season.

Peterson stayed on with Minnesota until 2017, when they declined to bring him back, and he signed a two-year, $7 million deal with the Saints. Fox’s Jay Glazer stuck Peterson with the pointed end of a question about how he would share duties with Mark Ingram after never sharing carries before in his career.

It turns out the answer to “Who will win touches between Mark Ingram and Adrian Peterson?” was “Alvin Kamara.” Just a few weeks after Peterson yelled at and stared down head coach Sean Payton on the sideline, Peterson was shipped to Arizona for a sixth-round pick. Peterson managed 448 rushing yards in six games with the Cardinals, but 293 of those came in two games in which he showed flashes of his old self, and he combined for 155 yards in the other four contests. On the whole year with both clubs, Peterson set career lows in attempts, yards, yards per attempt, and touchdowns for completed seasons in which he played at least four games. Arizona released him in the offseason, and Peterson struggled to find work. He didn’t catch on anywhere in free agency and wasn’t even invited to a training camp in July, so he held his own. The greatest running back of his generation was out of work, and seemingly out of the league, just before his 33rd birthday.

Then Guice tore his ACL and Washington signed Peterson to a one-year deal worth $1.02 million. Even at the time, many around the league doubted he had anything left (including yours truly). It is safe to say we were wrong.

He’s still difficult to bring down and possesses the power to run through defenders and enough speed to run by them. His 64-yard touchdown against the Giants on Sunday was the first 60-plus yard touchdown run for a player 33 or older since Jim Thorpe, who did it in 1921, just 10 years after the original Red Dead Redemption took place.

Here's the all-22 angle on the Adrian Peterson 64-yard TD run. Moses and Davis block down on play side DE/DT, Scherff pulls and kicks out S Collins, Roullier pulls and pins LB Davis. Huge lane for AP, then it's all about him outrunning the FS #Redskins pic.twitter.com/dEhp2lO33U — Mark Bullock (@MarkBullockNFL) October 29, 2018

Peterson’s success is allowing Washington to win despite a lesser air offense amid a passing boom (Washington has the lowest passing yards per game of any division leader). After finishing 28th in rushing yards per game last year, Washington is eighth this year, the highest mark of head coach Jay Gruden’s tenure, and Washington is 5-2 and in first place in the NFC East after two consecutive third-place finishes. Peterson looks like his old self, and thanks in part to his performance, it’s his entire team that’s now defying expectations.