LAS VEGAS -- TJ Dillashaw pulled off a stunning upset, dominating bantamweight champion Renan Barao until the fight was stopped at 2:26 of the fifth round at UFC 173 on Saturday night.
"I've dreamed it for so long, it's unbelievable," Dillashaw said. "If you can dream it, it can happen."
Dillashaw, a 9-to-1 underdog entering the fight, ended Barao's 35-fight unbeaten streak.
"Barao is the best in the world in my eyes," Dillashaw said. "I had to bring my 'A' game to become the champion."
The challenger utilized excellent footwork to attack from different angles, finding his range early and limiting the damage Barao was able to inflict.
Dillashaw (11-2) landed a hard overhand right in the second that hurt Barao, and nearly had him finished just before the end of the round. He maintained control throughout the next two rounds, switching between southpaw and orthodox stances while peppering Barao with a barrage of punches.
Dillashaw was well on his way to victory when he landed a left kick to Barao's head midway through the final round. Barao (34-2-1) fell to the mat and Dillashaw quickly followed with punches, forcing referee Herb Dean to stop the fight.
"That's who I am, I'm aggressive," Dillashaw said.
In the co-main event, Daniel Cormier dominated MMA great Dan Henderson (30-12), winning with a rear naked choke in the third round.
Cormier (15-0) is expected to challenge for the light heavyweight title and called out champion Jon Jones.
"Jones, you can't run from me forever," Cormier said. "If I decide to take Jon Jones down 100 times, I'll take him down 100 times. I'm coming!"
Jones is set to fight Alexander Gustaffson in a title rematch, with Cormier expected to face the winner.
On the undercard, top welterweight contender Robbie Lawler was dominant in a third-round TKO over Jake Ellenberger. Lawler (23-10) will likely earn another shot at the title.
"I wanted to go out there and showcase what I can do," said Lawler, who is fresh off a loss to champion Johny Hendricks. "I want everyone to know that I'm coming for the title."
Takeya Mizugaki will continue his climb up the bantamweight ladder after a unanimous decision over Francisco Rivera, and James Krause stopped Jamie Varner via TKO when Varner was unable to answer the bell for the second round due to a leg injury.
In the preliminary bouts, Michael Chiesa, Tony Ferguson, Chris Holdsworth, Mitch Clark, Vinc Pichel, Sam Sicilia and Li Jingliang each earned victories.