CLEARWATER, Fla. - The 30 pitchers in Phillies camp broke their circle and each took a few steps to pick up his glove. Cliff Lee found a spot among the two rows of hurlers and began playing catch with bullpen coach Rod Nichols.

This was the start of Lee's throwing program Wednesday. As he tossed a baseball for about 10 minutes, pitching coach Bob McClure watched by his side. Afterward, the 36-year-old lefthander retreated to a back field and threw his first bullpen session since the elbow setback that has put in question his season and could lead to the end of his playing career.

Lee made it through playing catch and the bullpen session but the discomfort in his pitching elbow is still there. The key is whether it remains minimal enough to where he can pitch through the tear in his common flexor tendon.

"If it starts to progress worse, then obviously that's a pretty telling sign," Lee said. "If it maintains how it is, then I'll keep going."

If not, any day could be the one in which Lee opts to shut it down.

As he said Tuesday, he will "play as long as I comfortably can. When it's uncomfortable to play and it hurts to play, then it's not worth it."

He will continue his throwing progressions Thursday at the team complex while teammates travel to Lakeland to play the Detroit Tigers.

"It [stinks], man," closer Jonathan Papelbon said of Lee's situation. "Everybody in this clubhouse knows what kind of great competitor he is and the knowledge of the game that he has to pass on to some of these young kids in this clubhouse.

"It's hard to kind of put into words. . . . But I do know that he's a great teammate, a great guy, and he's going to do what it takes to get back and do everything he can to get back on the mound."

Papelbon is on record as saying he's "not so sold" on the Phillies' rebuilding efforts given the presence of the many veterans still with the club.

If Lee isn't able to avoid surgery, "somebody's going to have to step up," Papelbon said.

"That's just plain and simple," he added. "Good teams have people go down and people have got to step up. That's basically what it boils down to."

David Buchanan and Miguel Alfredo Gonzalez would likely both slot into the April rotation if Lee can't pitch through the tendon tear. The two righthanders entered camp competing for the fifth spot in the rotation.

"He's a big part of our team," Cole Hamels said of Lee. "It's unfortunate. I know I've had to go through some of those types of situations earlier in my career. Thankfully, it hasn't been something as serious to where you're missing as much time as he's done.

"But I do know that he's a tremendous worker, and he's the type of guy who wants to be out there. I think he's going to do whatever he can to take care of his arm and his health and still be able to play the game of baseball that he's really good at."