The nicknames attached to boxing—the Sweet Science, the Manly Art of Self-Defense, the Fight Game—obscure the concussive violence at the heart of the sport. Then suddenly there's Manny Pacquiao—until then seemingly invincible—planking on the canvas in Las Vegas after a single right hand from Juan Manuel Màrquez, and we are reminded that boxing is all about punches thrown and landed.
Here's a look at where Màrquez's epic shot of Dec. 8 ranks among history's eight greatest one-punch KOs (that's one punch; no Dempsey-Willard mauling or Douglas-Tyson beatdown), rated on historical significance and sheer pyrotechnics.
1 Sugar Ray Robinson KO 5 Gene Fullmer,May 1, 1957
The fighter acclaimed as the best ever pound-for-pound, Robinson won back the middleweight crown with a textbook left hook, thrown while moving backward.
December 24, 2012
2 Rocky Marciano KO 13 Jersey Joe Walcott,Sept. 23, 1952
Marciano was a 9-to-5 favorite to take the heavyweight title from Walcott, but he was behind on points when he backed the champ to the ropes and landed a perfect right hand. Walcott, wrote A.J. Liebling, "flowed down like flour out of a chute."
3 Juan Manuel Màrquez KO 6 Manny Pacquiao,Dec. 8, 2012
In their fourth meeting (after a draw and two narrow Pacquiao wins), the battered and bleeding Màrquez finally provided a definitive ending.
4 Tommy Hearns TKO 2 Roberto Duràn,June 15, 1984
Size determined the result in this match between two alltime greats, as the 6'1" Hitman poleaxed the 5'7" Duràn with a huge right cross.
5 Floyd Patterson KO 5 Ingemar Johansson,June 20, 1960
Patterson became the first to regain the heavyweight title; his scythelike left hook left Johansson out cold, leg twitching, and Patterson shaken by his own viciousness.
6 Muhammad Ali KO 1 Sonny Liston,May 25, 1965
The rematch between Ali and Liston ended after less than two minutes amid chaos and cries of a fix. But Ali's flashing right—cynics dubbed it the Phantom Punch; he called it the Anchor—landed flush.
7 George Foreman KO 10 Michael Moorer,Nov. 5, 1994
Nearly 22 years after he first won the title, the 45-year-old Foreman concluded his improbable comeback with a thudding right that flattened Moorer and made Big George the oldest heavyweight champ in history.
8 Lennox Lewis KO 4 Hasim Rahman,Nov. 17, 2001
Upset by Rahman seven months earlier, Lewis came into the rematch fiercely focused. He stalked Rahman from the opening bell before pulling the trigger on a rifle shot of a right hand—the signature punch of his 14-year career.
Among heavyweight champions, current WBC king Vitali Klitschko has a KO percentage of 87.23 (41 of his 47 bouts, 45 of which were wins), second all time to Rocky Marciano's 87.76% (43 of 49, all wins).
Join the Debate on SI's App for Windows 8
• Launch the SI app for Windows 8 on your tablet or computer
• Tap or click on the 8 Debate live tile in the app timeline
• Watch exclusive video of George Foreman discussing the art of the KO punch