Washington Redskins veteran running back Adrian Peterson has a lot of experience in the NFL with which he can impart on younger players. San Francisco 49ers rusher Jerick McKinnon, a former teammate of Peterson's with the Minnesota Vikings who hasn't played a down yet for the NFC West club due to a recurring knee injury, has been working out with the all-time back in the offseason.

Via Matt Barrows in The Athletic:

“‘I feel like it’s my last test to really see how it feels,' McKinnon said. ‘There’s a lot of hard work going on down there. That’s really where I’m going to amp it up as hard as I can and see where it goes.'

“During a phone conversation with The Athletic on Wednesday, McKinnon said his knee feels normal and that he hasn’t had the pain or soreness that plagued him when he was trying to come back from the original injury last year. He said he’s being smart with his knee, but that he’s become confident enough in it that he’s ready to test himself alongside Peterson (now with Washington) and the crew that trains in Houston.”

McKinnon, 28, a former third-round pick-up by the Vikings in the 2014 NFL Draft out of Georgia Southern, suffered an ACL tear in Sept. 2018 following a four-year, $30 million deal signed with San Francisco in the previous spring. McKinnon later saw himself placed on the 49ers' Injured Reserve list for the 2019 season, further frustrating the running back's desire to get back on the gridiron.

Peterson, now with the Redskins at 35 years young and and the NFL's fifth all-time career rushing leader, has taken his ex-teammate McKinnon under his wing in order to best rehabilitate from the multiple obstacles sprout up by the ACL tear and knee surgery. Peterson once sustained an ACL tear with Minnesota during the 2011 season and his body of work — 13 years in the league, seven Pro-Bowl selections, and one MVP award — speaks for his experience recovering from the same injury McKinnon is currently working to get into form and help the 49ers.