The fight between Andre Ward and Allan Green scheduled for April 24 in Oakland, Calif., has been postponed because Ward is having problems with his surgically repaired right knee.

Ward reportedly will be out four to six weeks. A new date for the fight, part of the Super Six Boxing Classic on Showtime, has not been announced.

Ward reportedly tried to train normally but couldn’t go 100 percent because of pain.

Carl Froch fights Mikkel Kessler as part of the Super Six tournament on April 24. It will be televised in the U.S. on a delayed basis.