Best Welterweight Bouts in MMA History

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No. 6 -- Georges St-Pierre versus BJ Penn (UFC 58, March 4, 2006)

Photograph By Josh Hedges/Zuffa LLC/Getty Images

Penn returned to the UFC after a stint outside the organization to face St-Pierre. The French-Canadian hadn't won a title in the UFC yet, and no one really had a sense of how good he'd become. Penn put St-Pierre through the paces, battering and bloodying the future champ in the opening round. GSP showed his mettle, though, and took the next two rounds for a highly debated split decision. St-Pierre celebrated afterward in a Las Vegas hospital.