A gritty Russian racewalker won the solitary gold up for grabs on Wednesday as a world championships characterised so far by drama and disqualifications reached its midway point.

Olga Kaniskina grimaced her way through downtown Daegu to win the women's 20 kilometres walk title for a record third time -- in the process breaking a curious curse that had developed in this southeast Korean city.

For each of the previous four days of competition, the athlete who has featured on the cover of the official programme had suffered a shock, ignominious exit.

Day one, defending pole vault champion Steve Hooker exited without completing a successful jump; day two Usain Bolt was disqualified from the 100m final; day three Cuba's Dayron Robles was stripped of gold for bumping in the 110m hurdles and on Tuesday, pole vault queen Yelena Isinbayeva failed to win a medal after a miserable performance.

"I hope you are not on the cover tomorrow," the lissom Russian smiled to a table of fellow competitors as she left a Daegu cafe near the athletes' village on Wednesday.

Wednesday's cover star Kaniskina ended the hoodoo, though, with her third title, crossing the line in a time of 1:29.42.

"Thankfully no one told me about this before the race, they only told me after," Kaniskina laughed at a news conference.

"I didn't know about it, but it was a good decision to put me on the cover."

The curse, while it lasted, was a welcome distraction from the disqualifications which marred the beginning of the championships.

First the world's fastest man Usain bolt was scratched from the 100 metres final when he left the blocks too soon. Instantly peeling his vest off and slapping his hand against a wall, his title was taken by fellow Jamaican Yohan Blake.

Twenty-four hours later, Cuba's Dayron Robles sprinted to gold in the 110 metres hurdles, only to be instantly stripped of it for bumping great rival Liu Xiang along the track.

Instead gold went to Jason Richardson. Many felt the race should have been re-run as Xiang may have won gold had he not been impeded.

The Chinese ace could be forgiven for being a little bitter about the incident but when asked what he would say when he next saw Cuba's Robles, he instantly answered: "Hello buddy".

The disqualifications and the resulting fallout has split opinion in this south-east Korean city.

It is ridiculous -- do not deprive the sport, the fans and broadcasters of seeing the greatest of track and field performing in the greatest races, say one side of the argument.

Rules are rules, say the other side, including London 2012 Olympics chief and former track great Sebastian Coe who likens a disqualification to a knockout blow in the first round of a boxing bout.

"These things happen in sport," he said. "We mustn't get too hooked up on this. There's been DQs in the past, we have the rules, they're pretty clear, we don't play fast and loose with them simply because you get high profile DQs.

"There is no preordained outcome."

The controversy, though, is sure to spark much soul-searching among the highest echelons of the athletics world.

But for now they insist nothing will be changed and certainly the current one-false-start-and-you're-out rule is set in stone for London's Olympics next year.