Anniversaries in boxing are beguiling entities. It was always better back then, wasn’t it? Well, as millions of the committed and curious wait for Floyd Mayweather and Manny Pacquiao to provide at least fleeting evidence to the contrary in Las Vegas on 2 May, the calendar clicks on to mark the passing on Wednesday of 30 years since a night in that town when the sport held its breath for seven minutes and 52 seconds of glorious combat. Surely it could not get better than this …

When any combination of the Four Kings – Marvelous Marvin Hagler, Thomas “Hitman” Hearns, Sugar Ray Leonard or Roberto “Hands of Stone” Durán – shared a ring, as happened on nine memorable nights from 1980 to 1989, during their almost magical domination in gathering up a total of 16 different world titles between them, we needed little convincing that this was a rivalry matched for sustained excellence by very few in the history of the sport.

But the undisputed best battle of the four-sided war – an assertion not made lightly, given the personnel – was contained in just under three rounds between Hagler and Hearns on 15 April 1985. It took place at Caesars Palace, then the epicentre of the fight game, as Madison Square Garden – with no fruit machines and only seasonal warmth – ceded domain to the sunburnt gamblers in the desert.

Hagler was an out-and-out middleweight, a naturally stronger man in that division, but Hearns had grown from a skinny amateur with no punch into a feared finisher, the most celebrated graduate of Emanuel Steward’s Kronk gym in Detroit, one of his first champions and always his favourite.

If you were not there or have not seen recorded evidence, seek it out and decide for yourself if nostalgia has drowned out reality. The go-to referee of his era, Richard Steele, had little to do but watch and occasionally slip his arms into the middle of a breathing buzz-saw as the fighters skated over the Budweiser logo disputing the belts of the three recognised scallywag ruling bodies – the WBC, WBA and IBF – in an all-American cliche of which Norman Mailer would have been proud.

Britain’s best, 64-year-old Harry Gibbs from Bermondsey, was one of the three judges rendered surplus to the verdict, but, for the record, he and Herb Santos, a Vegas regular from nearby Reno, had Hagler up 20-18 after the two completed rounds, while the Californian Dick Young saw it for Hearns by the same margin.

Their judgment did not matter. Hagler decided it with his gloved rocks, his bullet-headed determination and a frightening relentlessness that reduced the lean, coiled power of the Hitman to reluctant impotence.

Facebook Twitter Pinterest Hagler, left, and Hearns pose for photographers during a January 1985 Boston news conference promoting their fight. Photograph: Elise Amendola/AP

Hagler had won the title five years earlier in similar fashion, slicing Alan Minter into bloodied submission inside three rounds at Wembley Arena, but his coronation that night was marred by racists who threw bottles into the ring, cowards in the dark who did not recognise greatness through bloodshot eyes.

For most of his career, the Brockton, Massachusetts, fighter had struggled for acceptance, an unfashionable southpaw whose angular, stiff-backed style appealed neither to TV executives or any of the losing opponents in his 59 wins on the way to a date with Hearns.

In his 15th fight, after a little more than two years as a pro, they threw him in with the unbeaten Sugar Ray Seales, expecting him to lose, and he prevailed. Yet another 34 bouts passed before Hagler forced the suits to give him a title shot, and, by general consensus, the champion, Vito Antuofermo, was fortunate indeed to draw and keep his WBC and WBA belts at Caesars in 1979. Antuofermo, though, could not beat Minter.

So, here was Hagler back at Caesars again, having defended his titles regally against such estimable opponents as Fulgencio Obelmejias (twice), Antuofermo (emphatically, this time), Mustafa Hamsho (twice), William “Caveman” Lee, Leicester’s Tony Sibson, Wilford Scypion and then Durán, seen off over the old 15-round journey. That was a defining performance and it would not be the last.

Hearns, who had stopped 26 of his first 28 welterweight opponents, came to the ring cloaked in awe, his only reverse a dramatic 14th-round stoppage by Leonard to unify the welterweight title. It was The Ring’s fight of the year in 1981 and defeat persuaded Hearns to move up to middleweight, where he was similarly destructive, famously knocking Durán out in two rounds in 1984.

Hagler, however, was as different from Durán (who had gone 15 rounds with Hagler 18 months earlier) as he was from all the others. He was a technician, awkward, obdurate, fearless, hard to read and virtually impossible to hurt. So, it heightened the shock when – after two postponed meetings not of his making – Hagler emerged from an early skirmish with Hearns that night in Caesars looking as if someone had ripped at his face with a can opener.

Facebook Twitter Pinterest Hearns and Hagler in action during the first round of their world title fight in April 1985. Photograph: AP

From the first bell, they traded on roughly equal terms, neither man looking for nor allowing rest. “Half a minute to go in round one, how far can this one go?” HBO’s Al Michaels screamed at his co-commentator, Al Bernstein. Hearns, pinned on the ropes, let his fists fly without caution from that launching pad, so powerfully he broke his hand in what The Ring called “the greatest round in boxing history”.

Steward, shouting above the roar of the 15,000 fans, pleaded with Hearns during the break: “You’ve got to stick and move.” Hearns was weakening from the effort of boxing on the retreat but still throwing bombs. No way was he listening to Manny tonight. Then in the third, still competing but horribly carved up around the eyes, he was nailed by a right hook he did not see and shipped a clinching cross from the same hand that decked him, forcing Steele to end the drama. Even the referee, more than likely, would have liked some more of this.

Hearns received a mere $200,000 less than the $5.6m the defending champion was paid. That’s the way it usually went with Hagler, all the way to his disputed loss in his farewell fight, on points against Leonard, who was the shiniest and most lauded of the quartet. To this day, Hagler is bitter about that call, although there is barely a peep of resentment from him at his home in Milan.

Facebook Twitter Pinterest Hagler knocks Hearns down in the third round in Las Vegas. Photograph: AP

Hagler knows how good he was. So do the others. And boxing folk always refer to this fight as Hagler-Hearns, not Hearns-Hagler. It is the ultimate accolade.

How the Guardian reported the fight

WJ Weatherby in Las Vegas

It was all over in eight minutes. After two minutes one second of the third round, referee Richard Steele decided Thomas Hearns could not take any more and Marvelous Marvin Hagler had won the 11th defence of his undisputed world middleweight title.

The Caesars Palace crowd, of over 15,000, many of them high on liquor or drugs greeted Hagler’s win with a storm of noise worthy of a football stadium. Despite the quick end everyone knew they had been present at a historic event, one of the most thrilling title fights of all time.

Although both fighters weighed 150lbs the battle of the giants proved to be an unequal fight between a fully grown middleweight and a super welterweight. As soon as Hearns accepted Hagler’s challenge to punch toe to toe - and probably he did not have much choice – the end was inevitable. Hagler proved he could take Hearns’ strongest punches in ferocious exchanges, but Hearns was eventually worn down by Hagler’s combinations.

Facebook Twitter Pinterest Hearns lies on the mat after being knocked out by Hagler in the third round at Caesars Palace. Photograph: Anonymous/AP

Yet if the fight had lasted much longer, it would have had a very different ending. Twice in the last round, the referee asked the ringside doctor to examine cuts above and below Hagler’s right eye that were streaming blood.

Although the doctor allowed the fight to continue Hagler must have realised it was only a matter of a round or two before the fight was stopped, and so into his final onslaught there was a great feeling of desperation. The worsening cuts were the price he paid for the non stop ferocious fighting of the first two rounds, but luckily for him Hearns wilted first.

“I just prayed to God to give me the chance and he did,” Hagler said afterwards. Hearns had seemed curiously off balance with almost a drunken stagger a couple of times in the second round, and he was obviously weakening from the power of Hagler’s punches. In the third round, immediately after the doctor gave Hagler a reprieve, the champion charged across the ring, caught Hearns with a powerful left and then a right that turned Hearns around and made him fall back in a dreamlike defenceless state. Hagler followed him across the ring and landed two more long, solid rights.

Hearns went down and lay unmoving on his back as if he were unconscious, but somehow he staggered to his feet by the count of nine. But his eyes were crossed and his legs wobbly, and when the referee immediately stopped the fight Hearns had to be helped back to his corner. Even at the post fight press conference, thought he did make an appearance and was lucid, he needed support at each arm.

Facebook Twitter Pinterest Hearns is carried from the ring as Hagler celebrates. Photograph: AP

If there is a rematch – but given the unequal strength between the two men this doesn’t seem likely – Hearns would certainly try to fight a different fight. He started this one ever confident - “cocky” as Hagler put it afterwards - and he fell into a Hagler trap in the first minute of the first round and never escaped.

In his training, Hearns seemed to convince himself that Hagler would make his usual slow start allowing Hearns to dominate and set the style. He came out in the first round as if he were facing the cautious Hagler who had fought Roberto Duran. Instead, Hagler immediately rushed across the ring and attacked him relentlessly and made him back up, taking the advantage away from him.

Hearns stunned him in the first round but could not follow up. “Box him Tommy,” Hearns corner men kept yelling, but there was no way Hearns could fight Hagler from a distance if his punches could not subdue Hagler and make him fall back.

Hagler, his face slowly becoming a mask of blood, kept up the pursuit, taking more and more risks to deliver his own punches. In this gambling town, Hagler turned the fight into a big gamble and won just in time.

• The two fighters will share an estimated $20 million.