(CNN) -- Andre Berto claimed the vacant World Boxing Council welterweight title when he halted Miguel Rodriguez in the seventh round in Memphis.
Berto took the WBC belt vacated when Floyd Mayweather retired.
Berto (22-0, 19 KOs) picked up the WBC belt that became vacant when Floyd Mayweather retired.
Rodriguez's record dropped to 29-3 with 23 KOs.
Berto floored Rodriguez with an uppercut in the seventh round and when Rodriquez went down a second time referee Lawrance Cole intervened at 2:13.
Dane Mikkel Kessler knocked out Dimitri Sartison in the 12th round in Copenhagen, to become World Boxing Association supermiddle champion .
Kessler (40-1) dominated throughout in front of an enthusiastic home crowd at the Brondby Hall.
Sartison, who was born in Kazhakstan but grew up in Germany, suffered his first loss after a 22-0 start in his pro career.
Kessler won the WBA title in November 2004 by stopping Manny Siaca of Puerto Rico.
He also lifted the the WBC super middleweight crown two years later when he knocked out Markus Beyer of Germany in the third round.
But he surrendered both belts when Joe Calzaghe of Wales ended his unbeaten run in Cardiff last November.
Britain's Amir Khan was floored before successfully defending his Commonwealth lightweight title with a fifth round stoppage of Michael Gomez in Birmingham.
Khan, who has won all 18 of his fights since turning professional after winning a silver medal at the 2004 Athens Olympics, knocked Gomez down in the first round but found himself on the canvas in the second in a brief but rugged contest.
Khan said: "This was one of my toughest fights but I learned from my mistakes. I will watch the video and work on them and continue my journey to the world title."
Khan was on target with a powerful right uppercut in the first round and a combination of punches floored Gomez, who retaliated in the second round.
A left hook over the top of a jab put Khan down and he had to take a standing count and looked unsteady on his legs for several seconds afterwards.
Gomez landed a damaging hook to the ribs in the fourth but early in the fifth Khan put his opponent down again with a powerful body shot.
Gomez began to take a lot of punishment and referee John Keane stopped the contest.
Gomez looked disappointed but appeared to be all but out on his feet.