Who defeated Ken Shamrock in the main event of UFC 40?

Tito Ortiz defeated Ken Shamrock in the main event of UFC 40.

The fight took place on November 22, 2002, at the MGM Grand Garden Arena in Las Vegas. Ortiz won by technical knockout after Shamrock’s corner stopped the bout between the third and fourth rounds. The contest was a highly anticipated meeting between Ortiz, the reigning UFC light heavyweight champion, and Shamrock, one of the promotion’s earliest stars.

The bout was promoted as a major generational clash. Shamrock had been away from UFC competition for several years while pursuing opportunities in professional wrestling and other combat sports, whereas Ortiz had become one of the UFC’s most recognizable champions.

This result is sometimes mixed up with Ortiz’s later rivalry with Chuck Liddell. Liddell eventually defeated Ortiz twice, but he was not Ortiz’s opponent at UFC 40.