The knee is the same knee that forces Lidge to start last season on the DL.
Lidge has struggled mightily for the Phillies so far this season. In 28 games, Lidge was 0-3 with six blown saves in 19 chances with a disturbing 7.27 ERA. His struggles came after going a perfect 41-for-41 during the regular season for the Phils in 2008.
Ryan Madson will most likely take over closing duties with Lidge on the mend. "Mad Dog" already has two saves this season in 29 appearances.
The Phils were carrying 13 pitchers so they replaced Lidge on the roster with veteran catcher Paul Bako who was called up from Double-A Reading and will supply another bat off the bench.