BOSTON (AP) – With a balky ankle and tight shoes, Curt Schilling took the mound on Friday, throwing batting practice speed in the bullpen during a steady rain.

And that was reason enough for the Boston Red Sox to be optimistic.

“He actually did pretty well — well enough where we’re just leaving the door open for his season not to be over,” Red Sox manager Terry Francona said Friday night after Game 3 of the ALCS was postponed by rain. “But that’s the extent of it right now.”

Boston trails 2-0 in the best-of-seven series against the New York Yankees. The game, if it’s necessary, was rescheduled for Monday, but when the series resumes on Saturday the Red Sox will have a better idea whether their ace has made his last appearance in the playoffs.

“This is the first step, and the next step is to see how he shows up (Saturday),” Francona said. “And from there, then we’ll see. … The door hasn’t been closed, but that’s where we’re at.”

Schilling, who led the major leagues with 21 wins, lasted just three innings and 58 pitches while allowing six runs in Boston’s 10-7 loss in Tuesday night’s series opener. It was his poorest postseason performance since 1993.

Red Sox doctors said the sheath that covers two tendons in Schilling’s right ankle is torn, allowing one of the tendons to slip out of its groove and rub against a bone. Schilling wasn’t uncomfortable while pitching Tuesday because he was injected with a painkiller, but he wasn’t able to push off the mound with his right leg, costing him velocity.

Schilling had a special high-top cleat made that would add support to his ankle and keep the tendon from moving. Two hours before the scheduled start of Game 3, he threw long toss in the outfield and then for about 15 minutes in the Red Sox bullpen, changing from high-top to low-top shoes to find one with the right fit.

“It worked good. It just hurt his toes,” Francona said. “All that stuff and we got the wrong size.”

Schilling has not been available for comment on either Thursday or Friday, but he called a local talk radio station on Thursday to say, “If I can’t pitch without altering my mechanics, then we’re going to have to win a World Series without me.”

“It’s doable, and if you’re a world champion club you’re going to find a way,” he told WEEI-AM. “And I believe we are, and I believe we will.”

But Schilling’s availability is crucial to Boston’s hopes of making it past the Yankees to the World Series.

With the rainout, Bronson Arroyo was slated to pitch in Game 3 on Saturday, Tim Wakefield on Sunday, Derek Lowe on Monday in Game 5- the game that had been Schilling’s to pitch.

That would have Pedro Martinez pitching on Tuesday in Game 6. If the series goes the full seven games and Schilling is not available, Arroyo, a 27-year-old without a full season in the majors, might have to pitch the decisive Game 7 at Yankee Stadium on short rest.

“Curt won 21 games and we won 90-something (98), so we have some pretty good guys,” pitching coach Dave Wallace said. “I’m sure Curt would tell you the same thing: We’ve got some guys that are looking to step up.”

If Martinez were brought back for Game 5 it would be on his normal four days’ rest. But that would force Lowe to pitch in Yankee Stadium instead of at home. He has an 8-4 record with a 4.55 ERA at home and a 6-8 mark with a 6.21 ERA on the road this year.

“We are trying to win the series,” Francona said. “That will be how we base our decision, solely; not to extend the series, to get to a certain game. It’s based on trying to win four games.”