Left offensive tackle Jared Gaither suffered a left arm injury that forced him out of practice Thursday morning and afternoon, but isn’t regarded as serious .
And left offensive guard Ben Grubbs is expected to be out for the next few days due to an ankle problem after undergoing offseason ankle surgery.
"Ben has some ankle tightness, and he just needs about three days of rehab," Ravens coach John Harbaugh said. “We’re looking at it right now, but we’re just going to get him out and just rehab the ankles and give him a chance to get the swelling down a little bit.”
With those two starters sidelined, first-round pick Michael Oher shifted from his right tackle assignment to the left side and Marshal Yanda took Oher’s place at right tackle.
And Chris Chester filled in for Grubbs at left guard with David Hale lining up at right guard next to six-time Pro Bowl center Matt Birk.
The Ravens are in need of some depth following offensive tackle Adam Terry being placed on injured reserve this week due to a knee injury that will require microfracture surgery, according to team officials.
INJURY UPDATE: Wide receiver Demetrius Williams returned to practice after missing the morning session with a minor concussion.
"Demetrius landed on his head, and they held him out for the concussion issue," Harbaugh said. "They have to pass those tests."
Also not practicing: wide receivers Mark Clayton (left hamstring), Marcus Smith (leg), Biren Ealy (groin) and Thomas White (hamstring), linebackers Terrell Suggs (left heel) and Tavares Gooden (undisclosed), defensive tackles Justin Bannan and Lamar Divens (hip flexor) and cornerback Samari Rolle (neck). Justin Bannan was given the day off.
Rolle, who remains on the physically unable to perform list, increased his activity level. He engaged in some backpedaling and running on his own in a helmet and shorts.
The former Pro Bowl cornerback doesn’t appear to be quite ready to return to practice, in Harbaugh’s estimation.
"It’s so hard to predict, but Samari says a day or two more," Harbaugh said. "It’s going to be up to the trainer, but there’s nothing major in there. It’s just a matter of a strengthening process where he can move the head around and feel good about it. We’ll keep him out of contact for a good stretch."
Cornerback Fabian Washington (right knee) seemed to aggravate his tendinitis condition during a drill, but eventually resumed practicing.
Defensive end Will Johnson (hamstring) returned to practice.
NO TWITTER BAN: Harbaugh indicated that he’s not going to ban players from using Twitter or other social networking sites, but is cautioning them to be careful.
"I’m not a fan of it, I’m not involved with it at all," Harbaugh said. "We monitor it. We know exactly what our guys are Twittering and what everyone in the league is Twittering. We made it clear to them that it’s public domain. When you get onto Twitter or Facebook, basically it’s like having a microphone right there. That’s how you’ve got to treat it.
"However you come across on Twitter, that’s how you’re going to come across to the public. Our mindset is not to ban Twitter. It’s not to ban any medium. What we’d like to do is have our guys understand that there are kids out there and they’re reading what you put on there just like you’re talking to a camera, and treat it with respect."
QUICK HITS: Wide receiver Justin Harper’s 80-yard touchdown catch on a perfect spiral from quarterback John Beck was the highlight of practice. Harper was unsuccessful, though, when he attempted to shoot the football basketball-style through the goalposts on his post-touchdown celebration, clanging it off the crossbar. "The John Beck pass to Harper, yeah, it was a great throw," Harbaugh said. "John had a bunch of nice throws. He had a few nice throws that weren’t caught as well, so it was a good day for him." … Harbaugh won’t be here for today’s afternoon practice while he attends Jim Johnson’s memorial service in Philadelphia, and special teams coordinator and assistant head coach Jerry Rosburg is in charge of practice. "Jerry knows what he’s doing, it’s not complicated," Harbaugh said. "Our guys will be fine. They’ll be happy I’m not around." … Harbaugh is testing his wits and, potentially, his health by covering kickoffs. "We had it all set up, [Tom] Zbikowski was going to block [Haruki] Nakamura, [Jim] Hostler was going to block [Prescott] Burgess right there on the inside and I was going to be wide open," said Harbaugh, who nearly recovered an onside kick. "And something broke down. I need to be honest with you, I got a little scared. I kind of had to cringe a little bit there."