Vemola Off UFC 155, Brunson In To Fight Leben

UFC middleweight Chris Leben

Derek Brunson set to fight Chris Leben at UFC 155

Strikeforce veteran Derek Brunson will step in to replace the injured Karlos Vemola in his fight with Chris Leben at UFC 155.

UFC officials announced the bout Wednesday. The fight will likely serve as the opener of the pay-per-view.

Brunson started his career off as a top prospect in the sport going 9-0, before suffering a split decision loss to Kendall Grove in June and then a 41-second knockout loss to Ronaldo "Jacare" Souza in August at Strikeforce: Rousey vs Kaufman.

Leben is coming off a yearlong suspension for testing positive for prescription painkillers after his loss to Mark Munoz at UFC 138. "The Crippler" has since gone in for treatments for his addiction and has been sober in training for the fight.

UFC 155 is headlined by a rematch of Cain Velasquez and Junior dos Santos for the heavyweight championship.

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