If there was plenty of controversy surrounding the first two fights, there was no disputing the third.
Saul 'Canelo' Alvarez retained his undisputed super-middleweight champion status with a points victory over Gennady 'GGG' Golovkin in Las Vegas on Sunday morning, and in the process, settled one of the most defining rivalries in modern-day boxing.
Roared on by the vast majority of the crowd inside the T-Mobile Arena, Alvarez controlled much of the fight from start to finish, landing freely and beating a slow and sluggish-looking Golovkin to the punch at almost every opportunity. The 40-year-old Golovkin had his moments, particularly in the ninth round and came on stronger towards the end of the fight, but Alvarez aways looked in control.
Despite finding his target with several crushing blows, Alvarez was unable to close out the bout inside the distance against an opponent famed for his granite chin, but this time there would be no debating the judges' scorecards, even if two of the scores were debatably close: Alvarez claimed the victory 116-112, 115-113, 115-113.
It was the perfect response from the 32-year-old Alvarez, who lost for just the second time in his distinguished career last time out when he made an audacious step up to light-heavyweight to face WBA champion Dimitri Bivol. The undefeated Russian is next in action against Gilberto 'Zurdo' Ramirez in Abu Dhabi in November.
"You have to continue to move forward," said Alvarez, whose rivalry with Golovkin had turned personal. "I have shown that defeats can show you can be great and you can regain your humility.
"He is a good fighter, a real fighter. I am glad to share the ring with him."
The Mexican and his Kazakh rival first fought in September 2017, at middleweight, in one of the greatest fights in living memory, which ended in a disputed split draw. The second bout, 12 months later, was equalling thrilling and went the way of Alvarez by the narrowest of majority points decisions.
Four years later, this grudge match was settled in emphatic fashion as Alvarez took a deserved points victory to inflict only the second defeat of Golovkin's professional career.
The return to 168 pounds clearly suited Alvarez, but Golovkin was left to rue a slow start in which he only sparked into life when it was too late.
Alvarez improved to 58-2-2 with 39 knockouts, but he said he knew in the first round he wouldn't get the KO he said he wanted.
"First round, I knew he's tough. He's a tough fighter," the Mexican said. "I need surgery, my left hand is not good. But I'm good, I'm a warrior, that's why I'm here. I can't hold a glass. It's really bad. But I'm a warrior."
The first couple of rounds were cagey with Alvarez throwing a lot but not finding the target as much as his output would suggest, although Golovkin's face started to redden thanks to Alvarez's jab.
The Mexican was firmly on the front foot throughout the first eight rounds, and a big right hook in the fifth smashed against Golovkin's chin, but the Kazakh was able to absorb the force and push his cause on against his far more aggressive opponent.
Golovkin started to show his age as Alvarez continued with a barrage of shots which attempted to break down his opponent's defence.
In the ninth round, Alvarez found himself against the ropes but Golovkin just couldn't make any inroads even though he had begun to throw more shots.
The last few rounds were frenetic, Golovkin throwing everything at his Mexican opponent but it was too little, too late as Alvarez held firm.
"It didn't surprise me," Alvarez said. "I know him, he's a strong fighter", adding that he is interested in a rematch with Bivol but first needs to get healthy.
"I need to rest my body," Alvarez said. "I need to rest my hand, my body, but I will come back stronger. It's very important. I will beat him."
Golovkin (42-2), meanwhile, dismissed the idea the defeat could send him into retirement.
"Remember, I'm still champion at 160," said the IBF and WBA middleweight world champion. "I come back guys, I'm still champion."