BRADENTON, Fla. - Pittsburgh Pirates left fielder Jason Bay is making a slower-than-expected recovery from an off-season shoulder operation and is expected to start the season on the disabled list.

With Bay expected to be out a few more weeks - the Pirates don't yet have a timetable for his return - utilityman Craig Wilson will likely get most of the outfield starts in his place. Wilson had been projected for part-time duty in right field and first base.

"It's not official yet, but we're going to be hard pressed to have him (Bay) ready for opening day," manager Lloyd McClendon said Thursday. "He continues to make progress, but it's slow."

Bay, acquired from the Padres in August in the Brian Giles trade, had surgery to repair a torn labrum in his right shoulder in December and was expected to be ready for the April 5 opener. But he has yet to appear in the field in an exhibition game, getting all of his spring at-bats as a designated hitter or a pinch-hitter. He is 3-for-14 in Pirates games, going 0-for-1 as a pinch-hitter Thursday against the Reds.

"I'm still hitting the balls I should, and I feel real comfortable. I've just got to back out there," Bay said.

Bay is one of the Pirates' two major question marks with the start of the season only 10 days away. Right-hander Rick Reed is recovering from back spasms and hasn't pitched in a major league exhibition since March 10, possibly creating an opening for Ryan Vogelsong to be the No. 5 starter.

With Bay unavailable so far, Raul Mondesi has shifted from right field to left field and Wilson has made a majority of the starts in right field. Wilson has 34 homers the last two seasons, 18 last season, but has yet to get more than 368 at-bats in a season as he searches for a full-time position. He started in right field, left field and first base last season and spent part of the season as catcher Jason Kendall's backup.

"If we start with Bay on the disabled list, I would imagine Craig would get bulk of playing time in the outfield," McClendon said. "I wouldn't consider a platoon situation."

That would be fine with Wilson, one of the Pirates' few power threats. With the exception of Mondesi, who had 24 homers with the Yankees and Diamondbacks last season, no other Pirates player except Wilson hit more than 16 homers.

"They're going to do what they think is best for the team and hopefully I'll make it tough for them not to put me in the lineup," Wilson said.

Bay had a minor setback in his recovery Wednesday when, after a video tape session, he and the Pirates discovered he was favoring his surgically repaired shoulder and had inadvertently altered his throwing motion.

"It wasn't me," Bay said. "It wasn't my normal mechanics; I was kind of babying it. I was throwing where the least amount of discomfort was. So we scrapped it, and just said, `Pick up the ball and throw it.' "

Other outfielders still with the Pirates are center fielder Tike Redman, plus backup Rob Mackowiak, rookie J.J. Davis, minor league free agent Andy Abad, who appeared in nine games with the Red Sox last season, and outfielder-first baseman-pinch hitter Orlando Merced.

Bay hit .287 with four homers and 14 RBIs in 30 games with the Padres and Pirates last season, with all but eight of his 87 at-bats with Pittsburgh. He homered twice and drove in eight runs in the first game of a Sept. 19 doubleheader against the Cubs, the most RBIs by a Pirates player since Hall of Famer Ralph Kiner had eight in a 1950 game.