Coghlan, last year's National League Rookie of the Year award winner, will go under the knife to repair a torn meniscus and is likely done for the season.
He was injured July 25 when he shoved a shaving cream pie in the face of teammate Wes Helms during a TV interview following the Marlins' 5-4 win over Atlanta in 11 innings.
Instead of immediately opting for surgery, Coghlan underwent a rehabilitation stint, but the effort has been deemed unsuccessful due to intense pain.
Coghlan hit .268 with five homers and 28 RBI over 91 games this season.
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