Marvelous Marvin Hagler’s death Saturday at 66, which was announced by his wife, Kay, on the Facebook page for fans of the fighter who legally changed his name to “Marvelous,” shook the boxing world so deeply not only because of his standing as an iconic middleweight of his or any generation.

It also was a body blow in the most disheartening of ways because the lasting image of Hagler in the ring was as an indestructible purveyor of the sweet science whose style was more about delivering punishment over and over again than impressing the judges.

“I am sorry to make a very sad announcement,” Kay Hagler wrote. “Today unfortunately my beloved husband Marvelous Marvin passed away unexpectedly at his home in New Hampshire. Our family requests that you respect our privacy during this difficult time.”

Born in Newark before his family moved to Brockton, Mass., Hagler went 62-3-2 with 52 knockouts, becoming a household name recognizable for his shaved head, southpaw stance and punching power that propelled him to becoming the undisputed champion of the world at 160 pounds.

Hagler was at the center of some of the most memorable prize fights of all time during boxing’s storied 1980s. He, Sugar Ray Leonard, Thomas Hearns and Roberto Durán, among others, pushed the sport to even greater popularity by shifting the focus to the lighter divisions.

Even though it lasted less than eight minutes, his bout with Hearns on April 15, 1985, outdoors at Caesars Palace in Las Vegas is considered among the greatest ever. Hagler won the fight billed as “The War” via technical knockout, but not before the fighters traded blows with impunity in the center of the ring.

The first round still resonates with boxing fans because of its nonstop action. It’s often called the most exhilarating three minutes in boxing history, with Hagler marching forward with purpose from the opening bell and tossing aside his tendency as a slow starter.

Hearns landed a blow that opened a cut over Hagler’s forehead, but Hagler continued to attack. Hearns revealed after the fight that he had broken his right hand.

“That first round took everything I had, man,” Hearns said in the ring after the fight.

The pace eased in the second round, but Round 3 produced one highlight after another, starting with Hearns reopening the gash Hagler had suffered in the opening round. The fight was stopped briefly as Hagler bled profusely, but referee Richard Steele signaled for it to continue.

Hagler regrouped to land a devastating right hook to the head, sending Hearns stumbling backward into the ropes. Hagler went in for the knockout, connecting with a right to the chin and a pair of uppercuts, sending Hearns crashing to the mat.

Hearns barely made it to his feet at the nine count, and Steele stopped the fight at 1:52.

That was the apex of Hagler’s career, which ended April 6, 1987, following a controversial split-decision loss to Leonard, who came out of retirement for the fight, the first of his career at middleweight, again at Caesars Palace.

Hagler was the aggressor throughout, switching from southpaw to orthodox, but Leonard deployed a strategy of attacking in the closing stages of rounds in an effort to sway the judges’ scorecards.

One judge scored the fight in favor of Hagler, 115-113, and another had it the same score for Leonard. JoJo Guerra, however, scored it for Leonard, 118-110.

Hagler announced his retirement in June 1988, saying he had given up on waiting for Leonard to grant a rematch. He moved to Italy to pursue an acting career, leaving boxing behind for good and never suggesting he would reenter the ring.

“I feel fortunate to get out the ring with my faculties and my health,” said Hagler, who was inducted into the Boxing Hall of Fame in 1993.

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