"It's some small tears. There were no significant, big tears anywhere," Lidge said. "You can either aggressively go in and remove the torn part, or wait a couple of weeks and see if it heals on its own."
Because there's no guarantee that waiting will fix the problem, the Phillies and Lidge opted for surgery, a partial medial menisectomy that removes all or part of the damaged meniscus. Lidge won't do much for the first week, then will begin long tossing.
The 31-year-old closer, who had surgery in October on the same knee, said he's optimistic of being ready for Opening Day.
"It's a smart procedure for us to do now," Lidge said. "The bad news is that it happened. The good news is that if everything goes as planned, I can still be ready for the
first game of the season. I think I can be ready.
"[But] if I have to miss the first couple of games to be smart, I will. Once the torn part is out, it's gone, and it won't bother you again or affect anything else."
When Lidge had surgery in October, the tears were discovered, but only repaired rather than removed, because the thought was they would heal naturally.
"[This procedure] is partially related to that, because they did some work on the meniscus on the inside," Lidge said. "They tried to repair it the first time without having to take anything out, so it would be good for the rest of my life. But at this point, it makes more sense, it's a lot quicker to take out.
"Once it's out, it's gone. The part that hurt me won't hurt again."
With Lidge's injury not expected to be long-term -- though he might start the season on the disabled list -- the Phillies won't plan anything dramatic, such as moving Brett Myers to the bullpen and signing a free-agent starter. Tom Gordon, who has plenty of experience as a closer, will fill in, with lefty J.C. Romero and righty Ryan Madson handling seventh- and eighth-inning work.
Still, Lidge remains optimistic of pitching in Grapefruit League games in March and hopes to be available for the regular-season opener, March 31 against the Nationals.