CHICAGO - In the midst of a season in which Michigan defensive back Troy Woolfolk switched positions from cornerback to safety and back again, there were bound to be mental errors.

As much as the positions seem similar, Woolfolk said they are quite different. So the constant movement led to an inadvertent good play on what could have been a touchdown-causing mistake.

“I was playing corner and one of the things at safety, in my job in a specific defense, is to play man on the running back,” Woolfolk said. “I was at corner and I just forgot about the receiver and I just tried to play man on the running back.

“Luckily, it was a run play.”

The play accentuated why Woolfolk wants to stick with one position, cornerback. In his dual role last year, Woolfolk was ninth on the team with 46 tackles, yet he broke up only one pass.

He returns as the most experienced member of Michigan's secondary, where the loquacious Texan hopes to impart advice.

“I have him at a spot that he’s comfortable at and he has a physical presence out there,” Michigan coach Rich Rodriguez said. “He’ll give us some leadership in the secondary. That’s a position as a whole that we don’t have a lot of experience, especially depth-wise.

“So guys like Troy that have some have to play at a high level to help the other guys.”

It makes Woolfolk the only certainty at a position group that struggled throughout 2009, a group that often looked slow and out of position especially as the Big Ten season wore on.

So in the preseason, as Woolfolk settles himself into a one role, he’ll be eyeing J.T. Floyd, who is expected to start at the opposite corner position, and a host of freshmen and redshirt freshmen - to make sure they are ready.

“It gives me more responsibility to help out other positions,” Woolfolk said. “When I see young corners making mistakes, I can help them but at the same time me being versatile and being able to play two positions, since I did it last year, I can help out some of the safeties who make mistakes.”

He can relay the story of his own error. He said it's one he said the coaches don’t know about yet, and it came on a play in which they actually praised him.

“I was playing man on the running back and it was like ‘Good job, Troy, you read that good,’” Woolfolk said. “I was like ‘Yeah, thanks coach, I studied the film.’”

Now, the rest of the defensive backfield will be studying him.

Michael Rothstein covers University of Michigan basketball for AnnArbor.com. He can be reached at (734) 623-2558, by e-mail at michaelrothstein@annarbor.com or follow along on Twitter @mikerothstein.