Jamaica's Usain Bolt easily outstripped American rival Justin Gatlin to claim his fourth consecutive world 200m title on Thursday and complete a rousing sprint double in Beijing.
Bolt clocked a world-leading 19.55 seconds to beat Gatlin by nearly two-tenths, thumbing his chest as he crossed the line to add the 200m to his 100m title at the world championships.
The clear victory extends Bolt's domination of sprinting which stretches back to when he took the world by storm at the 2008 Beijing Olympics, also at the Bird's Nest stadium.
Gatlin, who has served two doping bans and finished just one-hundredth of a second behind Bolt in Sunday's 100m, clocked 19.74sec, with South African Anaso Jobodwana taking bronze with a national record of 19.87sec.
The victory meant Bolt has now remarkably won 11 of the last 12 individual Olympic and world sprint titles dating back to Beijing 2008, his only blip coming after a false start in the 100m at the 2011 worlds in Daegu.
"There was no doubt," said Bolt, who has had pelvic problems this season and did not consider an attempt on his own world record of 19.19sec, set in 2009.
"I knew I wasn't in the shape for a world record. But when it comes to the 200m, I am a different person, I was beaten there only once.
"My four world championships gold medals in the 200m, this is a big deal, a great accomplishment."
There was drama after the race, however, as a shoeless Bolt was downed by a cameraman on a Segway electric scooter who had strayed too close to the Jamaican.
The cameraman mounted a fixed railing and slipped backwards, shooting the Segway from under him into Bolt's heels and making the newly-minted champion fall backwards.
Bolt got up gingerly and limped away before continuing his victory lap.
Gatlin, meanwhile, said his age had showed in the race.
"I feel tired. Going through three 100s and three 200s is taxing on the body," he said.
"I'm the oldest person in the field and am still running and running pretty well. To be able to run 9.74sec is a really good showing.
"I gave it all I could give."
Huge cheers greeted Bolt, wearing lycra shorts and singlet in the green, gold and black colours of Jamaica and placed in lane six, with Gatlin on his inside in lane four.
Applause also rang out for Gatlin, in a red one-piece suit, as the stadium comperes built up a boxing-match atmosphere at the packed Bird's Nest.
The American, as in the 100m, suffered from a slower start than Bolt, who shot out of his blocks. Gatlin, a renowned fast starter who hasn't lost over 200m since 2013 and has set personal best of 19.57sec this season, looked threatening coming off the bend.
But sandwiched between Britain's Zharnel Hughes and Jobodwana, Bolt, in fult tilt after an electrifying bend, responded by moving into his famed "drive phase", unleashing the full power from his long legs.
Unlike the 100m, when it came down to one-hundredth of a second to separate Bolt from Gatlin, there was a clear gap this time.
And Bolt knew it, thumbing himself in the chest as he crossed the line to complete a double many thought was in doubt when he missed six weeks of competitive action with pelvic pain.
Gatlin, in the form of his life at the age of 33, previously won world 200m gold in Helsinki before testing positive for testosterone and serving a doping ban between 2006-2010, an enforced rest he credits with extending his career.
Athletics has been mired in doping controversies, but Bolt, one of track and field's most tested stars, again stepped up to the mark to boost the sport's credibility and also cement his legendary status.