Sean O'Malley walks out of Boston as the new UFC men’s bantamweight champion after making good on his promise to finish Aljamain Sterling.

O’Malley (17-1 MMA, 9-1 UFC) became the second Dana White’s Contender Series veteran to win UFC gold after stopping Sterling (23-4 MMA, 15-4 UFC) in the main event of UFC 292 at TD Garden. The official time of the stoppage for the bantamweight title fight was 0:51 of Round 2.

With 25 minutes to work, neither fighter committed to much early on. The feel-out process lasted for a majority of the round, as they took turns controlling the center of the cage, while offering single strikes at a time, mostly leg kicks. Sterling was able to grab a hold of O’Malley’s leg late in the round to initiate a clinch, and land some short punches before the fighters returned to their corners.

The action picked up quickly in the second round. O’Malley slipped after a kick in the opening seconds, which gave Sterling an opening to look for a takedown. Sterling was quick to get in on the legs, but O’Malley slipped away.

A moment later, as Sterling rushed in with a left hand, O’Malley landed a laser of a right counter to send the champion to the canvas. O’Malley followed up with big hammerfists as Sterling attempted to stay in the fight, but the referee saw enough and called a stop to the fight.

“Doubt me now!” O’Malley repeated as he walked around the octagon while waiting for the official decision to be read.

During his post-fight interview, O’Malley admitted his nervousness ahead of the fight, while showing respect to Sterling by once again calling him the best bantamweight in the world. He then turned his attention to pondering a rematch against Marlon Vera, who won a unanimous decision over Pedro Munhoz earlier on the main card.

O’Malley entered on the heels of a split decision win over former champion Petr Yan at UFC 280, which was his fourth-consecutive win, and the only decision of his winning streak. Saturday evening, he returned to his finishing ways to stop Sterling and claim the division’s title.

Sterling suffers his first loss since 2017, when Marlon Moraes finished him with a knee in the first round. Since that moment, Sterling rattled off nine-straight wins, including capturing the bantamweight title and recording three title defenses.

Up-to-the-minute UFC 292 results include:

• Sean O’Malley def. Aljamain Sterling via TKO (punches) – Round 2, 0:51

• Zhang Weili def. Amanda Lemos via unanimous decision (50-43, 50-44, 49-45)

• Ian Machado Garry def. Neil Magny via unanimous decision (30-26, 30-26, 30-24)

• Mario Bautista def. Da’Mon Blackshear via unanimous decision (29-28, 29-28, 30-27)

• Marlon Vera def. Pedro Munhoz via unanimous decision (30-27, 30-27, 29-28)

• Brad Tavares def. Chris Weidman via unanimous decision (30-27, 30-27, 30-27)

• Gregory Rodrigues def. Denis Tiuliulin via knockout (elbows) – Round 1, 1:43

• Kurt Holobaugh def. Austin Hubbard via submission (triangle choke) – Round 2, 2:39 – to win “TUF 31″ lightweight season

• Brad Katona def. Cody Gibson via unanimous decision (29-28, 29-28, 30-27) – to win “TUF 31″ bantamweight season

• Andre Petroski def. Gerald Meerschaert via split decision (29-28, 28-29, 29-28)

• Natalia Silva def. Andrea Lee via unanimous decision (30-27, 30-27, 30-27)

• Karine Silva def. Maryna Moroz via submission (guillotine choke) – Round 1, 4:59

For more on the card, visit MMA Junkie’s event hub for UFC 292.

Story originally appeared on MMA Junkie