SAN FRANCISCO - It's a good problem to have. That's the baseball cliché about a lot of pitching depth, and it applies to the Phillies after they acquired Cliff Lee on Wednesday. But it is a problem nonetheless - what will the Phils do about their overcrowded rotation?

Having improved the staff, the team must decide which two of Pedro Martinez, J.A. Happ and Jamie Moyer belong in the rotation, which of the three would be most likely to help in the bullpen, and whether to retain Rodrigo Lopez for a relief role. Manager Charlie Manuel said yesterday that Lopez would be available in relief in about three days.

Lee, the 2008 American League Cy Young Award winner, represents an enormous upgrade at the top of a rotation that spent much of the first half of this season pitching inconsistently. Through the first few months of this season, the Phillies were a good-hitting, smooth-fielding team that hoped to overcome thin pitching. Cole Hamels was rusty, Brett Myers allowed home run after home run before injuring his hip, Joe Blanton was a constant victim of one bad inning, and Jamie Moyer finally seemed old.

Lately, though, Hamels has flashed that old World Series MVP swagger, Blanton has dominated the opposition, and Moyer has looked like the guy who hemmed and hawed his way to 16 wins last season. Happ, better than anyone expected since being promoted to the rotation in May, might find himself in the bullpen again.

The depth began to increase when the Phillies signed Pedro Martinez during the all-star break. It was a low-risk, high-reward move intended to replace Lopez in the rotation, and ensure against the possibility that general manager Ruben Amaro Jr. would not be able to add a pitcher before yesterday's trade deadline.

But Amaro did add a pitcher, and now he and the coaching staff must decide whether to exclude Happ, Martinez or Moyer from the rotation. Despite Happ's performance as a starter, the team appears to view him as the best reliever of the three, and the injury-plagued relief corps needs help.

The day the Phils acquired Lee, Amaro said that the club had not signed Martinez to be a reliever, though both parties were open to the possibility. Martinez's contract includes a games-finished clause, according to a baseball source with knowledge of the deal. That clause indicates that the bullpen is not out of the question for him, although that role may not be plausible for a 37-year-old with a thick medical file.

Pitching coach Rich Dubee has said many times that he does not see Moyer as a reliever. That would leave Happ as the likely candidate.

But there is another way to see the situation. The overworked and unhealthy bullpen would suffer if both Moyer and Martinez, neither of whom is likely to regularly pitch deep into games, were in the rotation. Plus, why take Happ, one of the Phils' best starters in recent months, out of a role in which he has thrived?

The rotation is set through Wednesday, when Happ is scheduled to start. Beyond that, the Phillies face important decisions, albeit ones they are glad to make.

Contact staff writer Andy Martino at 215-854-4874 or amartino@phillynews.com.