Golovkin (38-1-1) saw his streak of successful title defenses stopped at 20, leaving him tied with Bernard Hopkins for the middleweight record.
The fight was a rematch of a draw last September that left neither fighter satisfied.
Kazakh Golovkin, 36, thought he had perhaps done enough to get the decision.
"I'm not going to say who won tonight, because the victory belongs to Canelo according to the judges", he was quoted as saying by ESPN. He's a very good fighter.
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"I think he's scared".
Ringside punch stats showed a close fight, though they favoured Golovkin by a small margin. Golovkin was credited with landing 234 of 879 punches while Alvarez (50-1-2) landed 203 of 622. He's a very good fighter. "Hopefully there'll be a third fight". At times their heads were nearly touching, bringing hooks and uppercuts into focus, with Alvarez landing a well-placed right to the body in the sixth.
Both fighters were cut in the course of the bout, Canelo sporting a long laceration underneath his left eyebrow, with Golovkin cut around the right eye and with swelling to his high cheekbones.
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As of Saturday afternoon, about 752,000 homes and businesses were without power in North Carolina, along with 119,000 in SC . More than 100 people were rescued and up to 75 more were awaiting rescue on Saturday morning, according to a town official.
As for Golovkin, it seems likely that he'd want another fight in order to win his belts back. Even though he was not running this time, it doesn't mean he was controlling the fight. Sanchez told Golovkin after the eighth round.
'Some very close rounds that could have gone either way.
'There's two ways to fight to fight as the naturally bigger guy.
Golovkin was believed to have won the fight and the pair were due to face off again earlier this year, but Alvarez failed two drugs tests. A draw like many boxing writers had it.
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The Wilmington airport had a wind gust clocked at 105 miles per hour (169 kph), the highest since Hurricane Helene in 1958. Fortunately for House, he says this storm should not be a devastating event for the beach town in terms of loss of life.
The stakes are high as whoever wins will have a crack at taking on the victor of the main fight.