Mexico's undisputed super middleweight champion Saul "Canelo" Alvarez retained his titles with a unanimous victory over compatriot Jaime Munguia in Las Vegas on Saturday.

Alvarez, who received scores of 117-110, 116-111 and 115-112 from the three judges to seal the win, sent his opponent to the canvas in the fourth round, the first knockdown of Munguia's career.

"Jaime Munguia is a great fighter. He's strong, he's smart. But I take my time. I have 12 rounds to win the fight and I did. I did really good and I feel proud about it," Alvarez said after handing Munguia the first defeat of his professional career.

"He's strong but I think he's a little slow. I could see every punch... That's why I'm the best. I'm the best fighter right now, for sure."

Saturday's fight, which bettered Alvarez's record to 61-2-2, was the 33-year-old's first since beating American Jermell Charlo last year.

It was Alvarez's fourth time defending his WBC, WBO, IBF and WBA super middleweight titles. REUTERS