ST. PETERSBURG -- The Angels' dream rotation apparently will remain precisely that -- a dream.

Reality hit hard on Thursday when manager Mike Scioscia disclosed that Kelvim Escobar most likely will have to spend the balance of the season pitching out of the bullpen. Back into the rotation goes Matt Palmer, who was 5-0 in seven starts before yielding to Escobar for a much-anticipated start on Saturday night in Detroit.

Escobar pitched effectively, yielding two earned runs in five innings and said he "felt strong" after throwing 92 pitches. He talked optimistically about teaming with John Lackey, Ervin Santana, Joe Saunders and Jered Weaver in what Escobar envisioned as "the best rotation in baseball."

The days since his start haven't gone well. Pain has resurfaced in the shoulder, subjected to surgery to repair a labrum tear on July 29, and Scioscia is hoping to have the big right-hander available in the bullpen by the middle of next week.

"I went to see a doctor, and I didn't have good range of motion, up and back," Escobar said. "It doesn't look like I can throw 80, 90 pitches. But I'm confident I can still help the team in the bullpen. I'm going to do everything I can."

"It was always a possibility we would have to deal with," Scioscia said, his mood more subdued than usual before Thursday night's series finale against the Rays. "He has a condition in the back [of his right shoulder] where there's no nerve, and it's affecting the stability of his shoulder.

"Kelvim wanted to see if he could still start with it. He made a great effort. He doesn't have the stamina to start. He feels great up to a certain pitch count. It became apparent getting up to 75, 90 pitches, he doesn't have the stamina to do that -- right now. He got to the 90-pitch range and it was something he couldn't tolerate."

Scioscia said it appears Escobar will be in the bullpen for the remainder of the season and that there won't be time to build arm strength needed to start.

"This year, it seems that's where we're at," Scioscia said.

On Friday night at Angel Stadium against the Padres in Interleague Play, Palmer will be making his first start since May 30, when he went seven shutout innings against the Mariners.

An 18-game winner in 2007 with a repertoire matched by few pitchers, Escobar, 33, prefers starting but has experience in the bullpen. He has said he'll do everything he can to help the club in relief if that's where he has to make his place.

"I want to help this team win," he said. "It's not about me -- it's about the team."

The Angels clearly can use Escobar's experience and electric stuff in the seventh and eighth innings -- especially with Scot Shields' uncertain status with left knee tendinitis.

But Scioscia clearly wasn't finding any silver linings with Escobar's exit from the rotation.

"There's a fragile balance now with our rotation," Scioscia said, having lost Palmer as a fallback option. "There's a lot of confidence in Matty. Kelvim has shown he's a difference-maker. When he has his stamina, he's one of the best starters in our league.

"We don't have any other options now. If our rotation can stay together and get us to a point in a game, certainly an arm like Kelvim's is important in the 'pen. We're certainly down to our limit as far as depth in starting pitching.

"I don't think this is by any means a plus move. It's a move we have to make."

Shane Loux, on the disabled list since May 17 with right shoulder inflammation, said he is making strides with long toss and hopes to be on a mound throwing perhaps by late this weekend.

Loux, who is 2-3 with a 5.40 ERA, made six starts early in the season with Lackey, Santana and Escobar all sidelined.