The bad blood between Marvin Vettori and Karl Roberson finally had a chance to boil over Saturday night, and when it did Vettori let it all out.

Vettori (15-3-1 MMA, 5-2-1 UFC) submitted Roberson (9-3 MMA, 4-3 UFC) with a first-round rear-naked choke, then let out a handful of screams of jubilation after winning a fight that was rescheduled from May in Florida, when Roberson was pulled after struggles with his weight cut. This time around, Roberson missed weight entirely, but still made it to the fight – only to tap at the 4:17 mark of the opening round.

The middleweight bout was the UFC on ESPN 10 co-main event at the UFC Apex in Las Vegas. It aired on ESPN and streamed on ESPN+.

To no one’s surprise, the two didn’t touch gloves, but it took 30 seconds before Vettori threw the first real punch of the fight. He tried to get inside not long after, but then found himself needing to block a high kick from Roberson after a brief tie-up. Roberson tried a question mark kick and just missed, but then tied Vettori up and took him down. Vettori popped back up and pushed Roberson to the canvas a few seconds later and looked for an opening from half-guard.

When Vettori wrapped Roberson up with a guillotine choke, Roberson got back to his feet and pushed off the cage with both feet to eventually somersault his way out of danger. But Vettori got the position back and started raining down ground and pound while Roberson covered up. With 50 seconds left, Vettori took Roberson’s back and wrapped up a rear-naked choke. It was tight, and Roberson had to tap.

Up-to-the-minute UFC on ESPN 10 results include:

Marvin Vettori def. Karl Roberson via submission (rear-naked choke) – Round 1, 4:17
Charles Rosa def. Kevin Aguilar via split decision (29-28, 28-29, 29-28)
Andre Fili def. Charles Jourdain via split decision (29-28, 28-29, 29-28)
Jordan Espinosa def. Mark De La Rosa via unanimous decision (30-27, 30-27, 30-26)
Mariya Agapova def. Hannah Cifers via submission (rear-naked choke) – Round 1, 2:42
Merab Dvalishvili def. Gustavo Lopez via unanimous decision (30-26, 30-26, 30-25)
Julia Avila def. Gina Mazany via TKO (punches) – Round 1, 0:22
Tyson Nam def. Zarrukh Adashev via knockout (punch) – Round 1, 0:32
Christian Aguilera def. Anthony Ivy via TKO (punches) – Round 1, 0:59