BOSTON -- Pedro Martinez needed just 10 minutes of throwing Wednesday to learn what he and Boston Red Sox fans hope will save their season.

His shoulder feels fine.

	Martinez

Boston's ace was confident he'd take his regular turn in the rotation Saturday against Texas after leaving Monday night's 7-3 win over Tampa Bay in the fourth inning with a stiff right shoulder.

"Everything's fine," he said. "I'm very optimistic right now."

For five minutes, Martinez played long toss with pitching coach Joe Kerrigan in front of the Red Sox bullpen in right field. Then he walked a few feet into the bullpen and threw off the mound for another five minutes. Fastball, changeup, curve, everything worked.

"I just threw my pitches, threw everything over," Martinez said, "just like in a normal game."

For Martinez, a normal game is extraordinary. And with the Red Sox locked in a tight playoff race, his presence is essential for them to have a shot at their third straight postseason berth.

His 1.59 ERA is the lowest in baseball. So is the .170 batting average opponents have against him. And his 210 strikeouts lead the AL. He's 13-4 and the Red Sox have totaled just three runs in those losses while he's allowed only nine.

But on Monday, he served up a three-run homer to light-hitting Miguel Cairo in the third inning, then took himself out of the game after the fourth because of the shoulder problem.

Earlier in the season, he spent time on the disabled list with a strained muscle in his right side, but Martinez doesn't think that's necessary this time.

"I think I'm going to be out there on Saturday," he said. "It was probably something for one day."

Martinez said he felt fine in Texas, where he worked on his routine between starts, during the Red Sox three-game series, played in very hot weather, that ended Sunday.

But "I was cramping when I woke up" Monday morning, he said. "Probably dehydration or something. Maybe I slept on top of (the shoulder), but I also ran a lot in Texas, so that's probably why" his shoulder bothered him.

Now, though, he expects to take the Fenway Park mound Saturday in front of fans who will be thrilled to see him there.

"I'm going to keep on taking the medications and keep getting therapy," Martinez said, "but if I feel OK (Thursday) and I'm not sore, then it's 100 percent sure I'm going to go on Saturday."