UFC 137: Penn vs. Diaz

A Welterweight main event between Nick Diaz and B.J. Penn headlined the card after a chaotic reshuffling of the event. The show was originally built around Georges St-Pierre vs. Diaz, but Diaz was removed after missing a press conference, leading the UFC to book GSP against Carlos Condit for the title and Diaz vs. Penn in the co-main. A late injury forced GSP off the card, elevating Diaz and Penn to the main event. This was Nick's first fight in the UFC in 5 years and his last career win.