Jamaican Usain Bolt trumped American rival Justin Gatlin to retain his world 100m title in spectacular style on Sunday.
Bolt, also the double Olympic gold medallist and world record holder in the blue riband event, ran a season's best of 9.79 seconds in Beijing.
Gatlin, who has served two doping bans, was just one-hundredth of a second off Bolt, taking silver in 9.80sec with fellow American Trayvon Bromell and Canadian Andre de Grassse awarded bronze medals after both timing 9.92sec.
Tempered applause rang hollow round a packed Bird's Nest stadium when Gatlin, in a red one-piece suit, was introduced to the crowd.
Bolt, wearing lycra shorts and singlet in the green, gold and black colours of Jamaica, was placed in lane five, Gatlin in lane seven of the nine-lane track in the Chinese capital.
The towering Jamaican, who celebrated his 29th birthday on Friday, was greeted with massive cheers at the stadium in which he took the world by storm at the 2008 Olympics with a first treble gold -- he repeated the feat in London in 2012.
Chants of "Usain Bolt" rang around along with acclaim for China's Bingtian Su, Bolt raising his eyebrows at a classical piano rendition from a Chinese musician and checking out his beard as his face featured on the big screen.
In their first meeting over 100m since the last final in the Moscow worlds in 2013 when Gatlin also came in second to Bolt, the American actually suffered from a slower start than the Jamaican.
Gatlin, a renowned fast starter who hasn't lost over 100m or 200m since 2013 and has set personal bests for both distances - 9.74 and 19.57sec - this season, pegged equal with Bolt out of the blocks.
Sandwiched between Mike Rodgers in four and Tyson Gay in six, Bolt, head down for the first 40 metres, moved into his "drive phase", unbuckling his long, powerful legs, but didn't dare look across the field until a savage dip at the line saw him win a memorable race.
With allegations of widespread doping dominating the build-up to the worlds, the Jamaican's showdown with the sport's pantomime villain Gatlin was portrayed by some as a symbolic struggle of light versus dark.
Gatlin has served two doping bans and since his return to action in 2010 has won 2012 world 60m indoor gold, London Olympic 100m bronze and Moscow world silver, and is currently in the peak of his form at the age of 33 on the back of an unbeaten streak of 28 races dating back to August 2013.
Although Bolt is the first to decry the idea that he is the "saviour" of track and field, global athletics chiefs will no doubt, at least in private, heave a huge sigh of relief at his win.