However, so close was the finish, as Jackson lunged through the line in 13.04sec, ahead of Anier Garcia of Cuba and Dwaine Ross of the United States, that he was unsure of his achievement until it had been replayed on the big screen.
He rose from his haunches in acclamation and put both arms in the air before the emotions of the moment began to tug at his face. Tears of joy.
Jackson had described last night's race as his best opportunity to reclaim the title he had won in Stuttgart. Two of his big US rivals did not line up alongside him - Mark Crear, the fastest man this season, had been disqualified for two false starts in the heats, and the defending champion Allen Johnson, whom Jackson had describes as his "voodoo" man, had succumbed to a calf injury.
The nature of these championships changed dramatically at 7.40pm local time as Marion Jones, who had arrived here seeking four gold medals, clutched the base of her back on the left side and collapsed to the track in agony 50 metres from the line in her 200m semi-final.
Her husband, C J Hunter, who won the shot put gold on the opening day, smashed his fist down in dismay in the stands before racing down to join her as she was wheeled away from view on a stretcher, her face still a grimace of pain.
The stretcher was taken to the medical station inside the stadium, where she was being attended to by two doctors. Jones' coach, Trevor Graham, said she had been struck by a cramp in her back and her agent, Charlie Wells, said he would be issuing a statement in an hour. The athlete they call "Superwoman" appeared to have run full speed into a slab of kryptonite.
Jones' ambitions of winning the 100m, 200m, long jump and one of the relays here - as a prelude to her greater goal of five golds at the Sydney Olympics - got off to a predictable start when she won the short sprint in a championship record of 10.70sec. But, after having to settle for bronze in the long jump, she complained of fatigue as she made her way through the 200m rounds.
The American was diagnosed by doctors as having pulled a back muscle. The question now is whether she can recover in time to run in the Brussels Golden League meetting on Friday week, when she has to win to stay on course for a share of a $1m (pounds 620,000) jackpot.
In contrast, the rumours of injury surrounding the defending 400m champion, Michael Johnson, have disappeared, and the American - who ran 43.95sec in his semi-final despite appearing to ease down 100m from the end - is predicting a world record in today's final.
"I'm going to give it my best shot," said Johnson, whose best of 43.39sec - set in winning this title four years ago - is only 0.10sec outside the mark established by fellow American Butch Reynolds 11 years ago. "I've never run that fast shutting down so far out," he said. "I shut down with more than 90 metres left."
Julian Golding qualified smoothly for tomorrow's 200m final as he took third place in a semi-final won by Maurice Greene in 20.10sec. Golding finished with something to spare in 20.28. However, Greene's ambitions of completing a sprint double here were challenged by the performance of Nigeria's Francis Obikwelu in winning the other semi in 19.84sec.
As the IAAF - which late on Tuesday night announced the suspension of the Nigerian sprinter Davidson Ezinwa and the Somalian 1500m runner Mohamed Ibrahim Aden - attempts to come to terms with the doping issue, different problems face Lisa Misipeka, a bronze medallist in Tuesday's women's hammer competition.
Misipeka, who won the US Collegiate title last year, comes from the tiny island of American Samoa, which is likely to remain unaware of her achievement for some considerable time.
"I will call my father in California, and he will call my uncle in the family village, Fagatogu. From there the news will slowly travel round the island. It's still really third-world there. There is only one road on the island, and maybe only 40,000 people. I can't even imagine what their reaction will be when they hear of this."
Macey at his best;
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