With President Donald Trump sitting cageside, Ulberg delivered a perfect left hook to Jiri Prochazka’s chin and won the undisputed light heavyweight belt with a knockout at the 3:45 mark of the first round.

“I blew out my knee, but I never counted myself out,” Ulberg said. “I knew all I needed was that one shot and I ended up getting it. So I knew that Jiri was hesitant to come forward. And as soon as I landed my left hand he’s going.

“It’s about getting those moments.”

Ulberg (15-1-0) appeared to tweak something early in the first round when he planted his foot and his right knee buckled awkwardly. Prochazka (32-6-1) immediately went to work on Ulberg’s left leg, repeatedly landing leg kicks with hopes of taking both legs away, rather than attacking aggressively to end it.

“I felt sorry (for) him, and this is one of the biggest lessons in my life,” Prochazka said. “That fight was won, I had it, it was in my hands. I saw his injury, and … I will be back. Life is about that, learn and be better.”

The matchup was made after former champion Alex Pereira vacated the belt to move up and challenge for the interim heavyweight crown at UFC Freedom 250 at the White House on June 14, on what will be Trump’s 80th birthday.

Earlier, on his way to the arena, Trump’s Truth Social account posted an advertisement for the event.

Trump entered the Kaseya Center shortly after 9 p.m., accompanied by UFC president Dana White and several members of the Trump family.

As a Kid Rock song blasted from the speakers, Trump walked to his seat, where Secretary of State Marco Rubio was waiting. Also nearby was Sergio Gor, the U.S. ambassador to India.

Trump, who shared several smiles with the cameras, shook hands with attendees on the floor and made a point of greeting the UFC broadcast team, including podcaster Joe Rogan.

A crowd of onlookers could be seen filming the presidential motorcade upon arrival.

In the co-main event, Paulo Costa (16-4-0) used a right roundhouse to the head to drop Azamat Murzakanov (16-1-0) and end the bout at the 1:23 mark of the third round. Costa stepped onto the apron of the Octagon after his victory to shake Trump’s hand, and the president praised him. Costa acknowledged Trump during his post-fight interview with Rogan.

Josh Hokit (9-0-0) and Curtis Blaydes (19-6-0) battered each other in the slugfest of the night, with Trump excitedly watching the heavyweights as fans chanted “This is awesome!” as the fighters bloodied each other’s faces. Hokit won by unanimous decision (29-28, 29-28, 29-28).

White took to social media after Hokit’s win to reveal that a matchup between Hokit and Derrick Lewis had been added to UFC Freedom 250. According to White’s video, Trump asked why Lewis wasn’t on the White House card. White said he called Lewis and offered him a fight, and when Rogan jokingly asked during the broadcast if there was room for Hokit on the card, the match came together.

“President Trump built half of that fight, Rogan built the other half,” White said in the video. “Both guys have agreed and accepted the fight.”

In a light heavyweight clash, Dominick Reyes (16-5-0) defeated Johnny Walker (22-10-0) with a split decision (29-28, 28-29, 29-28).

Featherweight Cub Swanson (32-14-0) ended a celebrated career with a devastating first-round TKO of Nate Landwehr (18-9-0). The 42-year-old Swanson overmatched Landwehr with a bevy of punches to the head before referee Herb Dean stepped in to stop the fight with 54 seconds left in the opening round.