LAS VEGAS -- Rising bantamweight star Sean O'Malley's quest for a highlight-reel knockout was one-upped by the other worldly toughness of his late-replacement opponent.  

O'Malley (13-2) still recorded the victory via third-round TKO in a dominant and one-sided performance on Saturday's UFC 264 pay-per-view card, yet it was effort put in by a badly bruised and bloody Kris Moutinho that drew the most cheers by the end of the 135-pound bout.  

Referee Herb Dean jumped in to save Moutinho from further damage at 4:31 of the final round, setting off a cacophony of boos inside T-Mobile Arena. Moutinho, a 28-year-old native of Massachusetts who was making his UFC debut after replacing the injured Louis Smolka, likely secured himself a second date with the promotion as his forward pressure never slowed down despite accruing a tremendous beating.  

"Kris is a tough motherf---er," O'Malley said. "He took this fight on 11 days' notice when a lot of other UFC fighters wouldn't take this." 

O'Malley, 26, won his second straight since a TKO loss to Marlon Vera in 2020 and did so behind a huge jab that routinely punished his aggressive yet defensively neglectful opponent. Moutinho routinely walked into strikes of all kinds, including a left uppercut that dropped him in Round 1, a spinning high kick that later stunned him and a right cross that dropped him to close the round. 

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Although Moutinho appeared lucky he was saved by the horn when it looked as if he was closed to being stopped, he never stopped chasing O'Malley and sparingly landed single punches to slowly win over the same crowd that opened the fight chanting O'Malley's name.  

The final round saw Moutinho even mix in some trash talk as he continued to cut angles and get inside on O'Malley only to be stung repeatedly with clean strikes. A jumping knee to the face and a right cross from O'Malley late in the round set up the finish.  

"I was and I wasn't [surprised by the stoppage]. That's a lot of head damage from me," O'Malley said. "This might not be a good stoppage but it might have saved him [in the long run]." 

After the victory, O'Malley called out former champion Cody Garbrandt before accusing the entire division of ducking him.