Timothy Bradley battled to a split-decision triumph over Juan Manuel Marquez on Saturday to retain his WBO welterweight title.
Bradley remained unbeaten, and denied 40-year-old Mexican Marquez a world title in a fifth weight class.
The bout featured the last two fighters to beat Philippine ring hero Manny Pacquiao going head-to-head in a close, tactical contest.
To the jeers of a pro-Marquez crowd at the Thomas & Mack Center, two judges awarded the bout to Bradley, 116-112 and 115-113, while the third judge saw it 115-113 for Marquez.
Bradley almost sent Marquez down with a left hook in the closing seconds of the 12th.
The 30-year-old US champion was the aggressor through much of the fight, but he avoided the kind of brutal slugfest he endured in a unanimous decision victory over Ruslan Provodnikov in March that left him nursing a concussion.
Even so, Bradley said this decision offered no room for the kind of argument that greeted his controversial victory over Pacquiao in June last year.
“He couldn’t touch me,” Bradley said. “I gave him a boxing lesson.”
Marquez kept it close, and rocked the champion in the ninth, insisting he thought he had done enough to earn the victory.
“I know I did my job and I’m happy with what I’ve done,” said Marquez, who fell to 55-7 with one drawn and 40 knockouts. “I landed the best shots ... to win a fight, it’s not always necessary to win by KO.”
Marquez is no stranger to disappointing decisions. He endured two narrow defeats and a draw against Pacquiao before stunning “Pac-Man” with a sixth-round knockout in their fourth fight in December last year.
“I’ve been robbed six times in my career,” Marquez said. “I clearly won the fight.”
On the undercard, former champion Orlando Salido knocked out Orlando Cruz in the seventh round to regain the vacant WBO featherweight title.
Salido improved to 40-12-2 with 28 knockouts, while Cruz, who made headlines as the first openly gay pro fighter, fell to 20-3-1 with 10 wins inside the distance.
Two-time Olympic gold medalist Vasyl Lomachenko of Ukraine made an impressive professional debut with a fourth-round knock-out of Jose Ramirez in a scheduled 10-round bout.
Lomachenko won gold medals at the 2008 and 2012 Olympics. He also won world boxing titles in 2009 and 2011, along with a European championship gold medal in 2008.