UFC 121: Lesnar vs. Velasquez was a mixed martial arts event held by the Ultimate Fighting Championship on October 23, 2010 at the Honda Center in Anaheim, California, United States. The event was the fourth time the UFC has hosted at the Honda Center (formerly Arrowhead Pond) in Anaheim, California following UFC 59, UFC 63 and UFC 76 and the sixth event held in the Greater Los Angeles Area along with UFC 60 and UFC 104.