Boxing legend Marvelous Marvin Hagler died at the age of 66 on Saturday, his wife has announced. Hagler was the undisputed middleweight champion from 1980 to 1987.

"I am sorry to make a sad announcement. Today unfortunately my beloved husband Marvelous Marvin passed away unexpectedly at his home here in New Hampshire," Kay G. Hagler wrote on the boxing giant's Facebook page, adding "our family requests you respect our privacy during this difficult time."

Hagler one of the 'Four Kings' of the 1980s

Hagler's career lasted from 1973 to 1987, finishing with a record of 62-3 with two ties and 52 knockouts. During the 1980s, he was a member of the middleweight division's "Four Kings" alongside Thomas "Hitman" Hearns, "Sugar" Ray Leonard and Roberto Duran.

Hagler's 1985 matchup against Hearns at Caesar's Palace in Las Vegas is considered to be the three greatest rounds in boxing history. The match, known as "The War," is believed to be the zenith of Hagler's career.

"If they cut my bald head open, they will find one big boxing glove," Hagler once famously said, adding, "That's all I am. I live it."

'A true athlete and true man' 

"He was a man of honor and a man of his word, and he performed in the ring with unparalleled determination," legendary boxing promoter Bob Arum said of Hagler. "He was a true athlete and true man. I will miss him greatly."

Another legendary boxer, Oscar De La Hoya, said he was "saddened" by Hagler's death, calling him "one of the greatest to ever step into the ring."

Born Marvin Nathaniel Hagler in the US state of Massachusetts in 1954 and spending some early years in New Jersey, he took up boxing in 1969 after he was roughed up on the street by a local boxer. During his teenage years, he lied about his age in order to participate in amateur boxing tournaments.

Hagler was angered in 1982 after announcers did not use "Marvelous" when they said his name before a match. He then went to court to legally change his name to Marvelous Marvin Hagler.

Hagler lived in both New Hampshire and Italy. He had five children with his first wife, Bertha, and later married his second wife, Kay, in 2000.

wd/sms (Reuters, AP)