New York Mets right-hander Paul Blackburn underwent a procedure to repair a cerebrospinal fluid leak earlier this month and will be sidelined at least four-to-five months, the team announced Tuesday.

The surgery was performed by Dr. Wouter Schievink on Oct. 11 at Cedars-Sinai Medical Center in Los Angeles.

Blackburn, 30, landed on the 15-day injured list with a bruised hand on Aug. 25. The Mets shut him down in mid-September after the leak was discovered. At the time, the team said it didn’t believe it to be a long-term problem.

The Mets acquired Blackburn from the Oakland A’s at the trade deadline. He posted a 4-2 record with a 4.41 ERA in nine starts this season with Oakland before going 1-2 with a 5.18 ERA in five starts with New York.

Blackburn is 22-28 with a 4.85 ERA in 86 career games (82 starts) for the A’s and Mets.