Notre Dame coach Brian Kelly announced a few roster updates after Wednesday's practice.

Left tackle Jordan Prestwood left the team because of "personal reasons," Kelly said.

"Jordan is no longer with us, and I'm not able to get into the specifics about that because of privacy laws," Kelly said.

Prestwood was backing up starting left tackle Zack Martin. Freshman Ronnie Stanley filled in as the backup at left tackle, but Kelly said that was likely a one day thing and he hopes to redshirt Stanley this season.

"I hope he doesn't have to play, that would mean we had an injury," Kelly said of Stanley. "As you know, there are some moving parts on the offensive line, where we could move some guys around. I think we would need a couple of injuries for him to get on the field. But I don't want to take anything away from him, because he's been really good. He's been a pleasant surprise."

Running back Cameron Roberson, who was at practice in shorts and T-shirt, also will no longer play for Notre Dame. The junior injured his knee during a spring practice in 2011, and he has struggled to return to the field.

"Cam Roberson physically was not able to compete at the level that he felt was necessary to play here at Notre Dame," Kelly said. "We are going to pursue a medical hardship for him."

Wednesday's practice also had a pair of injuries, that Kelly wasn't able to give complete updates on because he met with the media shortly after practice ended.

Linebacker Danny Spond suffered what appeared to be a concussion, and tight end Alex Welch appeared to injure his knee, according to Kelly. But the coach couldn't provide more details because he didn't have time to meet with the medical staff before the interview session.