UFC president Dana White stated that a matchup between Diaz and UFC Welterweight Champion Georges St-Pierre was a possible consideration. Diaz and St-Pierre were rumored to be the next coaches for The Ultimate Fighter 14 reality show, but the show debuted on September 21, 2011, with Michael Bisping and Jason Miller as coaches. White later confirmed via Twitter that Diaz would face St-Pierre at UFC 137 at the Mandalay Bay Event Center in Las Vegas, Nevada, on October 29, 2011. Nick Diaz vacated his Strikeforce Welterweight Championship title prior to his bout with Georges St-Pierre. Dana White made the decision to take Diaz out of the fight and replace him with former WEC Welterweight Champion and future UFC Interim Welterweight Champion Carlos Condit, due to Diaz missing multiple flights for a press event to support the fight. It was announced that Diaz would fight B.J. Penn in the main event at his original fight card, UFC 137. Diaz won via unanimous decision. Diaz called out St. Pierre in the post-fight interview, who was scheduled to fight Condit at the same event but had been forced out of the bout with a knee injury.