Flawed drugs testing procedures forced international athletics officials to reinstate Russian Olga Yegorova to the world championships on yesterday despite a positive test for the blood booster EPO (erythropoietin).
The world indoor 3,000 metres champion was cleared to compete in Thursday's outdoor 5,000 metres first round after the International Association of Athletics Federations (IAAF) ruled that the test did not conform to International Olympic Committee (IOC) procedures.
There was further embarrassment for the IAAF when four leading sprinters were forced to change their shoes before the first round of the men's 100 metres because their spikes were too wide.
The federation later rescinded the decision and said athletes would be allowed to use the shoes for the remainder of the championships.
Yegorova's reinstatement raised the possibility of a boycott by Romania's Olympic 5,000 champion Gabriela Szabo, who threatened last week to pull out of the event in protest.
"It's really her decision," Szabo's agent Jos Hermens said. "But what can we do? It doesn't make a lot of sense to boycott because it will only help her (Yegorova) win a medal.
Senior IAAF vice-president Arne Ljungqvist told a news conference the IOC requirement for a joint blood and urine test had not been followed.
"I was taking for granted that a valid process had finished," he said. "For strict legal reasons we have no other choice but to lift the ban."
Yegorova told the news conference she had never taken EPO.
"Of course not," she said. "I think it must be a mistake, I was in shock."