Starting center Matt Birk is out three to four weeks after having minor knee surgery, and Casey Rabach won't be joining the Ravens after failing his physical.
But don't expect the Ravens to go after Olin Kreutz or Shaun O'Hara.
"Matt will be our starting center," coach John Harbaugh said. "I don't think he necessarily needs training camp. That's my feeling. Let him get this cleaned up right now, and we'll get a week or two of training camp with him, and he'll be ready to play."
Birk, 35, had surgery Tuesday to clean out the bursa sac in his left knee. If Birk didn't have the surgery now, it likely would have swollen up and bothered him the entire season.
"We decided to go ahead and get that cleaned up right now," Harbaugh said.
In a typical offseason, Birk might have had the surgery in February, March or April. But the Ravens weren't able to check him out until last week.
"He wasn't here, so you don't know what a guy looks like," Harbaugh said. "That's probably one of the negatives of having this whole situation."
Birk, the Ravens' starting center the past two seasons, hasn't missed a game since 2005. This isn't the first time he's had knee issues. In order for Birk to play 18 games this past season, his swollen knee had to be drained at least once a week.
The Ravens wanted to add Rabach for depth. But the former Ravens' third-round pick failed his physical because he hadn't recovered from offseason shoulder surgery.
One backup free-agent center remains on the market: Rudy Niswanger from Kansas City.
Undrafted rookie Ryan Bartholomew (Syracuse) practiced with the first team for the past two days, and Bryan Mattison could take over when he returns to practice Thursday.
If the Ravens are truly in a pinch, they could turn to Marshal Yanda, the versatile lineman who was the team's third-string center last year.
Not looking yet
There was no panic at Ravens headquarters after quarterback Marc Bulger announced his retirement Wednesday. Harbaugh had already estimated there was a 50 percent chance of that happening after the season.
So, will the Ravens jump on an experienced backup like Brodie Croyle, Jake Delhomme or Todd Bouman?
Based on Harbaugh's comments, it doesn't sound like it.
"This year, there are not as many guys available because of the late stage," Harbaugh said. "But there are a few veterans. I'm also confident that, in a week or two, there will be some veterans available if we decide to go that route. Right now, we want Tyrod [Taylor, rookie sixth-round pick] to get the reps and see how he does."
The three quarterbacks on the Ravens' roster are Joe Flacco, Taylor and Hunter Cantwell, a practice squad player from last season.
No trade for Umenyiora
The New York Giants have informed defensive end Osi Umenyiora that he is no longer allowed to seek a trade, according to the Newark Star-Ledger.
The Ravens were among five teams interested in trading for Umenyiora. Sources told The Baltimore Sun on Tuesday that the Giants demand for the pass rusher had dropped from a first-round pick to a second-rounder.
A 6-foot-3, 261-pound defensive end, Umenyiora has recorded 59 sacks in the past six seasons, including 11 1/2 last year. The Ravens had a total of 27 sacks as a team in 2010.
McClain goes to K.C.
Le'Ron McClain, a two-time Pro Bowl fullback for the Ravens, has agreed to a one-year contract with the Kansas City Chiefs.
The Ravens hadn't ruled out retaining McClain, even after they signed Vonta Leach, who was considered the top fullback available in free agency. But McClain chose to go to Kansas City, where he'll join a backfield that includes Jamaal Charles and Thomas Jones.
McClain becomes the ninth Ravens' free agent to sign elsewhere, joining tight end Todd Heap (Arizona), cornerback Josh Wilson (Washington), safety Dawan Landry (Jacksonville), nose tackle Kelly Gregg (Kansas City), offensive lineman Chris Chester (Washington), wide receiver Donte' Stallworth (Washington), cornerback Fabian Washington (New Orleans) and running back Willis McGahee (Denver).
The Ravens are one of five teams pursuing free-agent wide receiver Malcom Floyd. Minnesota, Arizona, San Francisco and Carolina are the others. … Ravens cornerback Domonique Foxworth (knee) and wide receiver Torrey Smith (hamstring) both returned to practice Wednesday after missing Tuesday's workout. The receiver group also welcomed back veteran James Hardy (hamstring), who also sat out Tuesday's practice. Ravens cornerback Jimmy Smith (groin), the team's first-round pick, missed practice for the second straight day. "We are just playing it safe right now," Harbaugh said of Smith. … If the collective bargaining agreement is approved, the Ravens' restricted and exclusive rights free agents will be able to practice for the first time in camp Thursday. "Either they will be allowed to practice or there will be another lockout or there will be some kind of compromise solution that they won't be able to practice," Harbaugh said before cracking a smile. "I am not betting on another lockout." … The Ravens were treated to ice cream when a couple of trucks pulled up at the end of Tuesday's practice. "It was Steve's idea," said Harbaugh, referring to owner Steve Bisciotti. "It was a great idea." … Hard-hitting safety Bernard Pollard is expected to sign with the Ravens on Thursday, according to Sports Radio 610 in Houston. Pollard played the past two seasons for the Houston Texans. The Ravens might need an extra safety because Tom Zbikowski (skin condition) is on the nonfootball-illness list.