Jamaica's Veronica Campbell edged the US' Lauryn Williams in a photo-finish to win the women's world 100m title yesterday.
Campbell and Williams clocked an identical 11.01 seconds with the judges taking several minutes to declare the winner, briefly plunging the event into confusion.
Carmelita Jeter claimed bronze for the US in 11.02, but there was disappointment for her teammate and former world champion Torri Edwards, who finished fourth.
Campbell, the Olympic 200m champion, made up for Jamaica's disappointment on Sunday when world 100m record-holder Asafa Powell was blown away by the US' Tyson Gay.
It was a deserved victory for the 25-year-old from Kingston, who ran the fastest semi in 10.99 and has the world's best time this year (10.89).
Jeter was a surprise medalist, although she had signaled her intent with the quickest time in the opening round.
But the predicted showdown between Campbell and Edwards failed to materialize.
The pair are the only women to breach the 11-second barrier this season with Edwards winning seven out of eight 100m races, her only loss coming at the hands of Campbell in New York.
Edwards, who took gold in Paris four years ago, has been in the form of her life this year after setting a personal best of 10.90.
Campbell, the Olympic 200m champion, has also been in scintillating form this season with three sub-11 second runs including the world's fastest time -- 10.89 in Kingston -- heading into the championships.
In 2003, Edwards finished second and third in the 100m and 200m, but was promoted to gold and silver after Kelli White's disqualification for doping.
Edwards was banned in April 2004 for taking nikethamide but was reinstated the following November when the substance was downgraded.
While the US dominated the opening weekend, Russia finally got on the medals table yesterday with a 1-2 finish in the women's steeple chase.
Yekaterina Volkova was already waving to the crowds with 80m to go and she finished in a championship record 9 minutes 6.57 seconds.
The silver medalist from 2005 held a margin of 2.62 seconds over Tatyana Petrova. Kenya's Eunice Jepkorir took bronze.
In a tactical team race, world record holder Gulnara Samitova-Galkina sacrificed her chances by setting the early pace before fading to seventh.
Japan's big medal hopes faded with Olympic hammer throw champion Koji Murofushi's sixth-place finish.
Ivan Tikhon of Belarus claimed his third straight title with a world leading throw of 83.63m on his last attempt. Primoz Kozmus of Slovenia took silver ahead of Slovakia's Libor Charfreitag.