UFC Tonight reported that a bulging disc in the back of Josh Koscheck has forced him out of a planned fight with Jake Ellenberger.

Koscheck and Ellenberger was expected to serve as the co-main event to UFC 151 on September 1.

UFC officials are working on finding a replacement for Koscheck, but with just a few weeks to go, that could be difficult.

Both Koscheck and Ellenberger are coming off defeats. “Kos” was topped by Johny Hendricks, while Ellenberger lost to Martin Kampmann. Interestingly enough, Hendricks and Kampmann are set to meet later this year.

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