Werdum bloodied Russow's face early in the clinch. He leveled Russow with an uppercut, then followed with several punches and hammerfists until the fight was stopped at 2:28 in the first round.
As the crowd chanted his nickname, "Vai Cavalo," Werdum jumped on top of the cage to celebrate and nearly fell off. Once he recovered, Werdum asked for a title shot against Junior dos Santos.
"I respect 'Cigano,' but I'm ready for him," Werdum said after the bout.
Werdum was knocked out by dos Santos when they fought in 2008. Since then, Werdum moved to Strikeforce, where he beat Fedor Emelianenko, but lost to Alistair Overeem. He now has two wins back in the UFC.
This is Russow's first loss since he was submitted by Sergei Kharitonov in 2007.
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