The 10 Most Productive Running Backs of 2015

8. Adrian Peterson, Minnesota Vikings

Rushing NEP: 3.82
Rushing Success Rate: 40.67%

Adrian Peterson came into the 2015 season with question marks galore. Would he be in top football shape after a year off? Would his age (30) be a detriment to his performance? Could he shoulder the 300-plus carry workload he was accustomed to handling before his year-long suspension in 2014?

Well, I guess we got our answer. And looking back, perhaps we shouldn't have doubted at all. All Day put together another superb season, tallying 1,485 yards and 11 touchdowns to go with seven 100-plus yard games on his way to his third rushing title.  And with 10 rushes going for over 20 yards (third most in the league), Peterson showed he still had the capability to bust loose just like he had prior to his suspension. 

Peterson's 0.01 Rushing NEP per rush fell short of his career averages prior to 2015 (0.03 Rushing NEP per rush), as did his 40.67% Rushing Success Rate, which stood at 41.77% prior to this season. But these are negligible declines in a player who is defying the odds based on his age. 

And Peterson's teammate, Jerick McKinnon, may help serve as a complementary force to help extend AD's career further. McKinnon's 8.83 Rushing NEP in 2015 actually would have landed him on this list had his sample size of carries (52) been large enough to qualify. So with a capable McKinnon spelling Peterson for breathers next season (and beyond), Peterson could easily continue his march into the history books as one of the best running backs ever to hit the field.