“Clinton knows that [he must work harder],” said Mitchell, the Redskins former running backs coach who accepted the head coaching position at Southern University on Monday. “He’s headstrong. He wasn’t getting the most out of his ability this past season because he did not prepare as well as he should have.”

And that led to Mitchell’s disappointment over the top-10 list.

“That was a hurting deal,” Mitchell said, “because now they’re saying they know Clinton better than I do. I wanted to prove those naysayers wrong. But they were right. I hope Clinton takes it to heart.”

Otherwise, he fears a repeat of 2009 when Portis was limited to eight games because of injuries and was ineffective when he did play. It won’t be Mitchell’s problem anymore.

“I didn’t want to go back to college,” he said. “But I always aspired to be a head coach. Hopefully one day I will come back in the NFL and be a head coach.”

Mitchell spent the past two seasons with the Redskins under coach Jim Zorn. He interviewed with new head coach Mike Shanahan on Monday before accepting the position at Southern.

He blames himself for the running backs’ lack of production this season; none of them averaged more than 4 yards per carry, partly because they ran behind a weak offensive line. Portis rushed for 494 yards in eight games.

“I was disappointed because a lot of people relied on us doing our job and for the most part we did not do that,” he said. “Guys have to take pride in their job.”

Guys meaning Portis.

“I love the way he plays at times,” Mitchell said. “But he’s not the guy he used to be. He still can achieve even more than in his best year. But in order to get that done you have to prepare. Some of these other guys are spending money at places away from their facility because in their minds they need something different and they’re busting their butt.

“I love Clinton. He’s a warrior. He could be the best back in the league. … I hope and pray that he busts his butt this offseason.”

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