Welterweight standout Anthony Johnson has been forced to withdraw from his main event meeting with Matt Brown at the season nine finale of The Ultimate Fighter on June 20.

A report from Fiveouncesofpain.com confirmed the news Monday afternoon, and Johnson subsequently issued an apology on his personal Myspace page.

"I'm sorry to everyone, my knee got jacked up training for my fight," Johnson wrote. "Not the best of times but I'll make it and come back stronger. I always do!"

Johnson last appeared at UFC Fight Night 17, defeating Luigi Fioravanti, his fourth UFC fight ended by KO or TKO.

A search for a replacement is currently underway.

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