OWINGS MILLS, Md. -- In order for the Baltimore Ravens to get down to the NFL roster limit of 75 players, two players from their 2012-13 Super Bowl championship team were sacrificed Monday: wide receiver LaQuan Williams and safety Omar Brown.

"Omar and LaQuan are two guys who have been here for a long time and have contributed so much to us," coach John Harbaugh said. "That's the toughest thing. They're going to play for other teams, I don't doubt that at all. A tough day, some tears, some hugs, and you come back out and go back to work."

The Ravens also placed three players on injured reserve: defensive ends Brent Urban (torn anterior cruciate ligament) and Kapron Lewis-Moore (torn Achilles) and offensive guard Will Rackley.

Rackley sustained a concussion during the first week of training camp, and he had a history of concussions when he played for the Jacksonville Jaguars.

The Ravens released linebackers Austin Spitler and Nick DiMarco, offensive tackle David Mims, cornerbacks Deji Olatoye and Marrio Norman, running back Cierre Wood, punter Richie Leone and wide receiver Mike Willie.

Offensive tackle Brett Van Sloten (sprained medial collateral ligament) and fullback Shaun Chapas (shoulder) were waived-injured.

The Ravens have until Saturday afternoon to get down to 53 players and will face some difficult decisions, particularly at wide receiver and in the secondary.

Harbaugh said seeing so many teammates gone tends to have an emotional effect on the remaining players.

"There's a feeling when you have fewer guys," Harbaugh said. "It started in the meeting. I walked in and I waited a little bit, and my first thought is, 'Everybody is not here. Do we have everybody?' It changes the dynamic."

--Ravens running back Bernard Pierce sustained a mild concussion when he was hit in the head Saturday night by Washington Redskins safety Brandon Meriweather.

Pierce didn't practice Monday. Before he can return, he must pass a mandatory baseline neurological test under NFL medical guidelines governing concussions. Pierce is slated to start the first two games of the regular season during running back Ray Rice's pending suspension for violating the league's personal-conduct policy.

Harbaugh said that Ravens trainer Mark Smith informed him that Pierce was feeling a lot better.

"Nowadays, with those things, I don't take any stock in that until they tell me that he's back," Harbaugh said. "The concussion thing is just hard to predict."

Veteran tight end Owen Daniels returned to practice, albeit on a limited basis, as he did only individual drills. The two-time Pro Bowler appeared to be doing all of the usual activities with the tight ends during the open portion of practice.

"He got back out there and ran around," Harbaugh said. "We don't want to bring him back too fast and throw everything on him, but he's working his way back in."

Daniels missed the past two weeks of practice and preseason games with leg soreness that Harbaugh repeatedly characterized as a non-injury.

Harbaugh emphasized that he expects Daniels to be a part of the team this season after signing a one-year, $1 million contract in March that includes no guaranteed money. Daniels was limited to five games last season with the Houston Texans due to a broken leg.

"I don't anticipate it affecting his status," Harbaugh said. "By definition of what's an injury, I just go by what the trainer tells me. There's no tear, there's no pull. There is swelling in the legs.

"That's probably the result of stress. Obviously, he's not right, or we would have played him. I'd be surprised if he doesn't practice on Friday fully."