The Baltimore Orioles believe left-hander Arthur Rhodes has the hard, nasty stuff to be a closer, which is one reason Manager Ray Miller elevated Rhodes to the role of co-closer 10 days ago. But they are less certain of whether he has a closer's makeup -- the ability to warm up quickly and enter tight situations several days in a row.

Rhodes was unavailable to pitch in today's 11-7 loss to the Philadelphia Phillies because of a stiff back, which was also bothering him Saturday night, when he walked the bases loaded in the ninth inning of a two-run game.

Miller said he learned of Rhodes's unavailability about 1 p.m., and said he was "not very happy" about the news.

However, Miller also said he will stay with his co-closer system of Rhodes and right-hander Mike Timlin, despite Saturday night's near-disaster. Rhodes walked the bases loaded with nobody out and Timlin surrendered a two-run homer in the ninth inning of an eventual 7-6, 10-inning win.

"That's what we've got, and that's who we're going to use," Miller said. "They both have the ability to do it."

But while Timlin has been a closer before, Rhodes has not, partly because of doubts about his ability to bounce back.

"If you're going to close, you have to be able to pitch three days in a row anyhow," Miller said. "The reason we haven't [used Rhodes in that role] in the past is it took him too long to warm up. . . . We're trying to work with him to speed up the process so it doesn't take so much out of him."

Rhodes's stiff back Saturday night may have contributed to his inability to throw strikes.

"He told me it was bothering him, and he spent the whole game stretching it," bullpen coach Elrod Hendricks said. "If your back is hurting, it might make you a little bit more cautious. When he warmed up, he seemed pretty free, and he said he felt fine. But if it was bothering him, he probably wouldn't have told me."

Rhodes declined to speak to the media today.

Ponson Heads to Funeral

Pitcher Sidney Ponson left the team today to attend the funeral of his grandmother in Aruba. Ponson will return Tuesday and is scheduled to pitch Friday. . . .

Cal Ripken's second-inning homer today was his 389th, tying him with Johnny Bench for 33rd all-time.