Felix Sturm regained his WBA super-middleweight title after securing a majority decision over Fedor Chudinov in their rematch on Saturday in Oberhausen, Germany.
Sturm handed the Russian his first professional defeat and made history by becoming the first German fighter to become a world title holder for a fifth time.
Judge Ignacio Robles scored the bout a 114-114 draw, while Jean-Louis Leglande and Giuseppe Quartarone both scored it 115-113 in favour of Sturm.
The 37-year-old forced the initiative, especially in the opening rounds, though Chudinov appeared to gain the upper hand as the challenger tired and the Russian seemed to be the fresher fighter after 12 rounds.
Sturm, who lost a split decision to Chudinov for the vacant title last May, hinted afterwards he could call time on his glittering career.
Cologne-based Sturm won the WBO middleweight crown in 2003 and has fought in 23 world title fights, including bouts against Brits Darren Barker, Martin Murray and Matthew Macklin
"Perhaps that was my last bout today. There was huge pressure. I'll give it a bit of time. We want to come down from this first," Sturm said. "All in all, it was a nice way to sign off if that was it."
Sturm improved to 40-5-3 (18 KOs), while Chudinov suffered his first defeat after 14 straight victories.
"Felix fought very well, very hard," Chudinov said. "There were a few clashes of heads, sometimes Felix's fault, sometimes mine. But I'm not in agreement with the decision."