Manny Pacquiao hailed Saul 'Canelo' Alvarez as the "pound-for-pound king" after the Mexican beat Caleb Plant to become the first undisputed world super middleweight champion.
Canelo knocked out previously unbeaten IBF champion Plant in the 11th round of their blockbuster showdown in Las Vegas on Saturday to cement his place in the record books.
The 31-year-old added Plant's belt to the WBA Super, WBC an WBO titles he already held, a clean sweep that has never before been achieved by a Mexican boxer.
He is just the sixth fighter since the WBO began sanctioning world title bouts in 1988 to hold all four of the belts.
Pacquiao won world titles across eight weight classes during his career and was among those to salute Canelo, who is now 57-1-2 on the back of a largely one-sided contest.
"Congratulations to the pound-for-pound king, Canelo, on making boxing history as the first undisputed super middleweight champion ever," Pacquiao posted on Twitter.
"Plant put up a great fight but Canelo is just too good. Boxing is in great hands."
Canelo went on the offensive from the off at MGM Grand and wore down Plant before brutally stopping his opponent with one minute and five seconds of the 11th round remaining.
It was Canelo's third stoppage win of 2021 as he further cemented his status as a boxing great.
WBC Interim world lightweight champion Joseph Diaz said: "What a fight, Canelo always closes! Respect to both fighters.
"Plant put on a great fight. We're witnessing true greatness what Canelo is doing in his career."
Plant more than held his own in the early rounds and was embraced in the ring by Canelo at the end of the fight.
That was in stark contrast to two months ago when the pair were involved in a physical altercation during a media conference to announce the fight.
Canelo revealed at the time the scuffle was down to a comment made by Plant regarding his mother, but he is nevertheless full of respect for his opponent.
"We don't have to take anything away from Caleb Plant. He's a great fighter and he made a great effort tonight," he said at his post-fight news conference.
"But in the end we came out with the win. That's all that matters really. So even though we had that frustration in the first five rounds the second half of the fight was ideal.
"He told me afterwards that he wanted to keep fighting and he also wanted to apologise to me and he didn't mean what he said about my mum. He was truly sorry about that.
"I told him: 'Look, it's OK. It's water under the bridge.' I told him he was a great man and also that some day I hope he will have a great family as well.
"I can only wish the best for him. In the fight we have to hurt each other but, in the end, we're all human and we want the best for each other."