Jermell 'Iron Man' Charlo made boxing history when he knocked out Brian Castano to win the WBO super welterweight title.
In winning the belt, Iron Man unifies it with the WBC, WBA, IBF titles for the first time ever in boxing.
He is only the seventh person from any weight class to hold all the belts of a single weight class from the four major boxing sanctioning bodies.
The others were Bernard Hopkins (middleweight), Jermain Taylor (middleweight), Terence Crawford (super lightweight), Oleksandr Usyk (cruiserweight), Josh Taylor (super lightweight) and Saul 'Canelo' Alvarez (super middleweight).
Charlo and Castano fought to an enthralling but unfortunately controversial draw in 2021 and it seemed as if this bout was headed in a similar direction after the pair split the opening rounds.
However, Charlo grew stronger as the fight went on where Castano looked to start tiring around the eighth round.
The American pounced on a couple of openings to land a hard right hook followed by a left to the head to sent Castano sprawling to the canvas.
Seizing his advantage, Charlo did not let up and immediately went in for more when Castano was back on his feet.
A strong left to the face saw the Argentine's head snap back before another left to the body sent him to the floor to end the bout.
"This is unbelievable," Charlo said. "I gave it my all and that was the end result of it. This was nerve-wracking. It felt like my first fight, where you get nervous. I had ants in my pants.
"I knew Castano was going to give it his all, and I trained very hard. I was in great shape.
"I was pretty sure he was going to get back up because it was only the first knockdown -- but I knew it was over," Charlo said
Castano showed he had no hard feelings after the fight and praised his opponent for a good bout.
"Everything that happened in the ring tonight, we showed that we are warriors," he said.
"We both were fighting back-and-forth. It was power back-and-forth and then his right hand came over and stopped the fight. He's a champion. He hit me. He got me. But I'm okay."