Adam Wainwright joined the 20 win club Monday night at Wrigley Field. (photo/MLB)

Adam Wainwright joined the 20 win club Monday night at Wrigley Field. (photo/MLB)

St. Louis Cardinals ace Adam Wainwright underwent surgery on his right elbow on Friday.

The club revealed that the 33-year-old submitted to a procedure which trimmed cartilage from his pitching elbow. After an initial MRI failed to reveal any significant issue, Wainwright pushed for a second MRI and the results spurred the decision to go under the knife.

Wainwright finished the 2013 season with a 20-9 record and 2.38 earned run average in 227 innings over 32 starts for the NL Central champions.

He missed a turn in the rotation in mid-June due to trouble with the elbow, though an MRI taken then revealed no structural damage to the ligament which was replaced with Tommy John surgery in 2011.