LAS VEGAS -- UFC welterweight champion Kamaru Usman promised he would take out his dislike for Colby Covington all over the Octagon inside T-Mobile Arena on Saturday. 

It turned out he was a man of his word. 

Usman (16-1) outboxed Covington on the feet for nearly five rounds of an epic two-way duel before finishing him via fifth-round TKO to defend his 170-pound title at UFC 245. Covington fought through a broken jaw in Round 3 and finished the fight a bloody and swollen mess after being dropped twice in the final round. 

"This one is not just for me but for the whole entire world right now," Usman said. "I heard all week, all month since the fight got signed that Colby was in my head and this or that. I'm telling you right now the reason I'm the best in the world is because my mind is stronger than anyone in the division."

Considering the fight was a pairing between arguably the two best wrestlers in mixed martial arts, it was surprising that neither attempted a single takedown in what turned into a five-round kickboxing match. Usman faked a takedown in the opening round but ultimately relied on his jab and power shots.

"I was catching him with left hooks," Usman said. "I was kind of overreaching and made a lot of mistakes tonight. My coaches told me to settle down and work behind the jab. Sometimes I come in here and just dominate with my wrestling and don't stay with my striking long enough. But I'm the best in the world and am going to keep improving."

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Usman, a 32-year-old native of Nigeria, extended his winning streak to 15 in the first defense of the title he won by dominating Tyron Woodley at UFC 235 in March. But he needed every bit of his world-class cardio and toughness as he combined with Covington (15-2) to set a hellacious pace that barely ever slowed throughout the fight as they traded punches. 

The 31-year-old Covington originally protested the stoppage from referee Marc Goddard and ran out of the Octagon after Usman was announced as the winner. Covington was dropped twice in the final minute of the fight thanks to big right hands before Goddard waved the bout off at 4:10.

The loss snapped a seven-fight win streak for Covington as he took his villainous and trolling character change and nearly rode it to a world title. The fight featured constant ebbs and flow in terms of punches traded although neither fighter went down throughout the first four rounds. Twice Covington appeared hurt from big right hands early but was able to weather the storm with a sneaky lead left hand to regain distance control.

The two shared plenty of bad blood in the lead up to this fight, nearly coming to blows in a few encounters with Covington poking at Usman with his heel character and calling him "Marty Snoozeman". That animosity continued in the Octagon where each questioned the other for eye pokes and low blows.

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UFC 245 updates, highlights

UFC 245 card/results

Kamaru Usman (c) def. Colby Covington via fifth-round TKO (strikes)
Alexander Volkanovski def. Max Holloway (c) via unanimous decision to win featherweight title (48-47, 48-47, 50-45)
Amanda Nunes (c) def. Germaine de Randamie via unanimous decision (49-44, 49-46, 49-45)
Marlon Moraes def. Jose Aldo via split decision (29-28, 28-29, 29-28)
Petr Yan def. Urijah Faber via second-round TKO (head kick)
Geoff Neal def. Mike Perry via first-round TKO (punches)
Irene Aldana def. Ketlen Viera via first-round KO (punch)
Omari Akhmedov def. Ian Heinisch via unanimous decision (29-28, 29-28, 29-28)
Matt Brown def. Ben Saunders via second-round TKO (elbows)

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