Portis back at practice, still needs to try contact

Updated: October 1, 2003, 6:40 PM ET

DENVER -- Clinton Portis was back at practice Wednesday, but the Broncos won't know if their starting running back can play this week until after he tests his bruised chest in contact drills.

Portis ran without any problems during drills Wednesday and will see if he can handle being hit in a workout Thursday.

"There was no setback, but until he actually goes through a practice where there's contact it's really hard to know for sure," Broncos coach Mike Shanahan said. "We'll definitely get some contact tomorrow for him to play on Sunday. We'll see if he can take some shots and hold onto the football."

Portis bruised his chest Sept. 14 against San Diego when Chargers safety Kwamie Lassiter hit him under the pads. He returned the next week against Oakland, but aggravated the injury after landing on his shoulder in the first half.

Portis took just two snaps in the second half against the Raiders and sat out last week's game against Detroit.

The Broncos also are holding out hope that center Tom Nalen will be able to return from a sprained ankle suffered late against the Lions on Sunday.

Nalen was walking better Wednesday, but still had a limp and didn't practice. He will likely be held out on Thursday before testing it Friday.

This story is from ESPN.com's automated news wire. Wire index