It was enough to make every elite-level middleweight of the day run for their lives.

On March 25, 1989, then-IBF 160-pound champion Michael Nunn scored an astonishing one-punch knockout of Sumbu Kalambay at the Hilton Hotel in Las Vegas.

After establishing distance over the first minute, Nunn deflected a Kalambay jab with his right glove, stepped outside his opponent’s left foot and unleashed a rocket left hook to the jaw. Kalambay went down like he’d been struck by lightning and didn’t come close to beating referee Richard Steele’s count. The official time of the stoppage was 1:28.

The Nunn-Kalambay bout was originally made as a unification matchup. Kalambay had won the vacant WBA middleweight title by outpointing Iran Barkley, in October 1987, and had defended successfully against Mike McCallum, Robbie Sims and Doug DeWitt. However, the WBA stripped the Congolese-born Italian for not facing British contender Herol Graham, a fighter he’d beaten before.

Despite Kalambay’s obvious quality, the hype surrounding Davenport, Iowa’s Nunn led to him being installed as a 5-1 pre-fight favorite. Quick and impeccably talented, the 6-foot-1 lefty was 32-0 and already established as one of the finest fighters in the world. Nunn was expected to win, but Kalambay (46-3-1) had never been stopped.

One punch and it was all over.

The moment was both a blessing and a curse for Nunn. The likes of Sugar Ray Leonard, Roberto Duran and Thomas Hearns were all still active at the time, but who the hell needs a slippery southpaw that can whack out an elite-level middleweight in less than 90 seconds? Despite calling for bouts against three of the Four Kings, Nunn was left outside the palace gates, perpetually ignored by boxing royalty.

Nunn KO 1 Kalambay was the first official Ring Magazine Knockout of the Year. Over the past 33 years, there are very few KO of the Year winners that have matched it for quality and shock value.

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