BALTIMORE -- The Orioles went out of their way to make a roster move Thursday, when they shuffled one weary arm for a fresh one just two days before rosters expand for the season's final month. Baltimore designated Rob Bell for assignment and purchased Jon Leicester's contract from Triple-A Norfolk in an effort to give the bullpen a needed refresher.

Bell, who took the decision in Wednesday's 12-inning loss to the Devil Rays, will be exposed to waivers and could be lost if another team claims him. If not, the Orioles will have 10 days to trade, release or assign him to an affiliate. In the event that Bell clears waivers, Baltimore manager Dave Trembley said that the O's plan on bringing him back as soon as they can.

"I thought it was self-explanatory for him. He wasn't going to pitch tonight [and] he wasn't going to pitch [Friday]," Trembley said. "We're hoping he clears waivers in three days, which takes us to Tuesday. We'd certainly like to add him back to the roster for September, but he's got to go through that protocol of clearing waivers, and Monday wouldn't count because it's a holiday. He knows that. If he clears, he'll join us in Tampa [on] Tuesday."

Bell, who has served as a long reliever for the last three months, has seen his statistics take a major turn in the last 10 days. The veteran had a 4.18 ERA on Aug. 22, but he's allowed 12 earned runs in his last four outings. Bell will head to the waiver wire with a 6.49 mark, a number that may keep other teams from identifying him as someone who can help them.

"It's frustrating," he said, "It feels like a week's worth of bad outings kind of skews the numbers and makes it look like the season's a lot worse than it has been. I feel like I've been a player that contributes, but they have to make tough decisions all the time about a lot of different players. These guys have given me an opportunity since Spring Training, and I'm grateful."

Bell washed out as a starter with Cincinnati, Texas and Tampa Bay before reinventing himself as a reliever, and he posted back-to-back effective months in June and July. He's been asked to work more than an inning in more than half of his appearances, and the strain may have caught up to him -- and the rest of the bullpen -- in August.

"I respect what those guys do a lot more now," he said. "And after watching our starting pitchers, I respect them for going out there and grinding every start. Sometimes, as a starting pitcher -- which I'd been for a long time -- you take the bullpen for granted. Pitching's a difficult job all the way around at this level of the game, and it's very satisfying when things do go well."

Bell certainly wasn't alone in struggling during the last week, but the Orioles thought he was the best candidate to expose to waivers for a variety of reasons -- chief among them his heavy workload in the last few days.

"We just need a pitcher for tonight and maybe for the next couple days," Trembley said, detailing his relief situation. "I'm not going to pitch [Chad] Bradford tonight, I'm probably going to stay off [Jamie] Walker and I'm going to stay off [Danys] Baez. ... [Kurt] Birkins has thrown two nights in a row. He probably hasn't done that in a long time. He went down to Norfolk and was a starter. We've got guys who are going above and beyond as far as we keep running them out there."

One day later: Trembley was much more composed Thursday and offered an explanation for his brusque press conference Wednesday night. Trembley, who's generally a very media-friendly manager, said that he just wasn't up to answering questions after his team played to its eighth straight loss on a trying homestand.

"I think I've been -- as you guys have been -- as accommodating, as open, as forthright as possible," he said. "And I think [Wednesday] night, it was best that I say as little as possible, and that's the approach I took. I've never said no to any guy here. I've never criticized any guy here for what they write or say about me or this team. And I never will, because I know that's your job, but there are times when I need a little space, too. I'm a human being, and I'm not afraid to admit that."

The players have taken it hard, too, but they've tried to minimize the effects as much as possible.

"I played for Tampa Bay for three years," Bell said. "I've been through stretches of ugly baseball, but there's a lot of quality players in here. You hope that there's a point when a hard line drive just gets hit at somebody.

"When things are going bad, they're unfortunately viewed as being worse. And when things are going real good, sometimes you think they're going better than they are."

Extra bodies: The Orioles expect to be active on Friday, when they're allowed to exceed the traditional 25-man roster. Baltimore will call back Bell -- if he's still in the organization -- and Garrett Olson, who's scheduled to start on Saturday in Boston. And they could also bring up a few more players to help fill in the gaps for the rest of the season.

"I would think there are probably four or five others that are coming when the Minor League seasons are over," Trembley said. "We're not done discussing the pitching. I don't know how many it's going to be. I think we're done with position players. There may be another addition of a pitcher, but we're not final on that yet."

Quotable: "I had seen enough. I wasn't going to cross that line and say something I shouldn't say. There's only so much self-control we can exhibit, and I think I've done a pretty good job of that." -- Trembley, on his brief press briefing

Coming up: The Orioles will send rookie Radhames Liz to the mound in Friday's 7:05 p.m. ET series opener at Fenway Park, and the Red Sox will counter with knuckleballing veteran Tim Wakefield.