Joe Nicholson-USA TODAY Sports

Watch: Adrian Peterson knocks out sparring partner in preparation for fight with Le'Veon Bell

There was a time when Adrian Peterson and Le'Veon Bell were two of the best running backs in the NFL, and they were certainly high on most fantasy football draft boards.

Peterson will be a Hall of Famer one day and Bell certainly made a name for himself during his time with the Pittsburgh Steelers.

The two former running backs aren't as prolific in the boxing ring, though, which makes their upcoming fight — whenever it may be — quite intriguing. 

It's also intriguing to see that Peterson clearly has some "oof" behind his punch. Below is an unverified video of Peterson with his sparring partner. He's apparently throwing haymakers, even in practice.

At 6-foot-1, 220-pounds, Peterson's strength as a football player was quite literally his strength. He was a brick house coming through the A-gap. He just also so happened to be a brick house with breakaway speed in open space.

Bell had some punch in him but he was more known for his ability as a "dual-threat" back, able to make defenses pay on the ground and in the air.

Notably, neither player has officially retired from the NFL, but they're clearly moved on to other things with the season just weeks away.

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