Yoan Pablo Hernandez defeated defending champion Steve Cunningham by a split decision after six rounds to claim the American's IBF cruiserweight title on Saturday.
Referee Mickey Vann stopped the bout after the sixth round because of two cuts sustained by the Cuban after the fighters twice clashed heads in earlier rounds.
Two judges awarded the fight to the 26-year-old Hernandez, 58-55 and 59-54, while one gave it 57-56 to Cunningham, who was making the second defense of his title in his second reign as IBF champion.
The fight looked to be over in the first round when Cunningham was knocked down, but he got back up.
Hernandez, based in Germany the last six years, improved to 25-1 with 13 knockouts. The 35-year-old Cunningham dropped to 24-3 with 12 knockouts.