UFC 90: Silva vs. Côté was a mixed martial arts event held by the Ultimate Fighting Championship (UFC) on October 25, 2008 at the Allstate Arena in Rosemont, Illinois

 
The Knockout of the Honors

 
Dos Santos’ UFC debut took place at UFC 90: Silva vs. Cote on the main card against top-ranked Heavyweight Fabricio Werdum. Werdum had been promised a shot at the UFC Heavyweight title, until it was put in the back-burners because of Randy Couture’s return to the promotion. Many saw Junior dos Santos as an easy win for Werdum, to hold him over until he could get his title shot. Little was known about dos Santos at the time, except that he was trained by Antonio Rodrigo Nogueira.

 
Werdum’s road to a shot at the Heavyweight title was derailed at 1:21 in the first round when dos Santos landed an uppercut, knocking Werdum unconscious. The win was considered a major upset, as many had never even heard of dos Santos. The KO earned dos Santos the Knockout of the Honors.