SANTA CLARA, CA - SEPTEMBER 14: Adrian Peterson #28 of the Minnesota Vikings looks on from the field during their NFL game against the San Francisco 49ers at Levi's Stadium on September 14, 2015 in Santa Clara, California. (Photo by Thearon W. Henderson/Getty Images)

Report: Adrian Peterson is still a free agent for only one reason

Anyone want one of the best running backs of his generation?

Adrian Peterson lead the league in rushing just two seasons ago, racking up 1,485 yards.

But teams seem concerned that's not the Peterson they'd be getting if they sign him to an expensive contract.

RELATED: There may not be much of a market for Adrian Peterson

ESPN's Jeremy Fowler reported this tidbit on Friday:

Fowler didn't say what Peterson wants, but it's got to be a chunk. Remember, he wanted the Minnesota Vikings to pick up his #18 million option for this coming season. The team smartly said that's too much for a 32-year-old running back who appeared in just three games in 2016 as he recovered from knee surgery.

So, if he wants to keep playing, it looks like he'll have to lower his demands.