"The War" was the nickname given to this bout by promoter Bob Arum, widely considered one of the most brutal fights in boxing history.
By 1985, "Marvelous" Marvin Hagler had been the undisputed champion of the middleweight division since September 27, 1980, after having been widely regarded as the No. 1 challenger for much of the late 1970s. His first two shots at the world middleweight title resulted in controversy: the first was an unpopular draw against then-champion Vito Antuofermo in 1979 (allowing Antuofermo to retain the title), and the second was a three-round technical knockout (TKO) of Alan Minter, in London, which led to a riot by Minter's fans. The hard road to the middleweight championship, however, may have helped motivate Hagler to remain dominant during his reign. Hagler was renowned for his conditioning and durability, suffering only one official knockdown in his career, against Juan Domingo Roldan, an incident Hagler always insisted should have been ruled a slip. By the time he fought Thomas Hearns, he had defended the title ten times, winning all but one by knockout; the sole Hagler defense that went the distance was a 15-round decision victory over Roberto Durán. Hagler was then approaching the middleweight record of 14 title defenses, held by Carlos Monzón.
When Hagler vs. Hearns took place, Hearns had recently moved up from the welterweight to the junior middleweight to the middleweight division. Hearns was regarded as one of the hardest punchers of all time, winning 30 of his first 32 bouts by knockout. In Hearns's first title shot in 1980, he scored a spectacular second-round knockout over WBA champion Pipino Cuevas. Hearns defended that title three times before meeting Sugar Ray Leonard in a thrilling fight dubbed "The Showdown." Hearns lost by technical knockout in the 14th round despite leading on all three scorecards. He then successfully campaigned at junior middleweight, winning the WBC title from Wilfred Benítez, and defeating Roberto Durán by a dramatic second-round knockout, the first knockout loss of Durán's career. Hearns defeated several middleweights during this period, including Marcos Geraldo by first-round knockout. Geraldo had gone the distance against both Leonard and Hagler.
Hagler, normally a slow starter, stormed Hearns from the opening bell, eventually pinning him to the ropes. Hearns threw his devastating right hand to Hagler's chin, stunning Hagler for a moment before Hagler was able to tie him up in a clinch. Hearns broke his hand delivering the punch. Seconds later, however, the two were trading power punches, with Hagler trying to get inside and to pin Hearns to the ropes again. In the process, he succeeded in stunning Hearns with a hard right hand. Hearns tied up Hagler again and tried to slow the pace by boxing rather than trading power punches with Hagler, who was still the aggressor. This lasted for only a moment, however, before long the two once again started to trade power punches. The slugfest continued for the better part of the next two and a half minutes as both fighters traded heavy blows with little regard for defense or pacing. Hagler developed a cut on his forehead, but didn't slow as he pinned Hearns to the ropes and meted out more punishment, eventually hurting Hearns at the end of the round. Sportscaster Barry Tompkins, doing the fight blow by blow broadcast for HBO's version of the fight, yelled out "This is still only the first round!" as the fighters traded heavy shots at round's end. This opening round is considered by The Ring as the greatest round in boxing history, and won round of the year honors for 1985. In a subsequent HBO broadcast featuring both Hagler and Hearns in studio commenting on the fight, Hearns revealed "...that first round took everything I had, man...". When asked in the ring after the bout if he was hurt by Hearns' first right hand, a blow that caused him to step back and then fall into a clinch, Hagler commented "...he definitely tried to put the bomb on me...he can punch...".
By the beginning of the second round, it looked as though Hearns had no legs under him as he slowed the pace by boxing Hagler. Hearns stumbled several times as he attempted to move around the ring and change direction prompting HBO commentator Sugar Ray Leonard to note "...I don't like the way Tommy's moving...a little rubbery-legged..." In the studio broadcast of the fight, Hearns commented "...my legs were gone, man...even before I came out to fight, my legs felt weak." Hagler experimented by switching to orthodox style for a moment, but switched back to southpaw as he found more success countering Hearns' jab. By the end of the round, Hagler pinned Hearns to the ropes, successfully landing a volley of punches. The action in round two had slowed from the blistering pace of round one.
Third and final round
In round three, Hearns again tried to set the pace. About a minute into the round, the cut on Hagler's forehead inflicted during the first round opened up, resulting in a tremendous flow of blood down the middleweight champion's face.
Referee Richard Steele halted the action to have the ringside physician examine Hagler. He informed Steele "...no the cut's not bothering his sight, let him go." Facing the new threat of losing the fight via stoppage on cuts, Hagler attacked Hearns with an aggression reminiscent of the first round. A tremendous overhand left to the head drove Hearns back to the ropes. Hearns backed away, smiling so as to suggest the punch had not hurt him. Hagler landed a hard right hook high on Hearns' head. The blow staggered Hearns who awkwardly stumbled backwards into the ropes, Hagler running after him in hot pursuit. The champion smashed a vicious right hand off Hearns' chin. Tommy went limp and fell forward as Hagler landed two uppercuts. As Hearns fell face first to the canvas, Sugar Ray Leonard yelled into his microphone "He's gone...he's gone!..."
Hearns staggered to his feet at the count of nine but was unable to continue. Referee Steele stopped the bout as he held Hearns upright. The image of a blood-soaked Hagler being carried around the ring in victory by his handlers and Hearns being carried back to his corner in semi-consciousness remains, to this day, graphic testimony of the intensity of "The War." It was widely regarded as the pinnacle achievement of Marvin Hagler's career and cemented his legacy as one of the greatest middleweights of all time.
The Ring called the fight "the most electrifying eight minutes ever" and it won fight of the year for 1985, despite lasting only three rounds.