Yet more talk of the lab rather than the track surfaced in Edmonton yesterday. The plot surrounding Russian distant runner Olga Yegorova thickened further, the fate of 800-metre contender Fabiane Dos Santos was decided forever, and the Canadians were again trying to clean up their image after 34-year-old sprinter Venolyn Clarke was caught taking the same drug as Ben Johnson.

While the word is that Yegorova may yet have to sit out the 5,000 metres, Dos Santos is definitely out of the 800 metres. She had become one of the pre-race favourites after winning in London the week before Edmonton but the Brazilian federation then quietly announced that the test done on her after the Rio Grand Prix on May 6th showed illegal levels of testosterone.

Under the IAAF two-strike rule, the 25-year-old now gets banned for life because of a previous doping offence back in 1995.

Dos Santos was given 48 hours to give her side of the story and apparently confessed to drug use. She lives and trains in Spain and, aware of her fate, did not travel to Canada for the championships.

The case of Yegorova may not be decided until hours before she lines up for the 5,000 metre heats later today. According to some sources in Edmonton yesterday, Yegorova is about to be re-suspended for using the blood-boosting EPO having been reinstated last week despite evidence of the illegal drug in her system after the Paris meeting last month.

The official IAAF statement claims that 50 athletes have so far been tested for EPO just before and during the championships, and Yegorova was one of them. According to IAAF vice-president Arne Ljungqvist, about 10 of those tests, including Yegorova, show red blood cell outside normal parameters.

"You can get these abnormal concentrations for other reasons," he said. "These are borderline values and we must make sure with further tests on the athletes' urine samples."

The announcement of those results are expected anytime between now and the start of the race, but Ljungqvist also stated that other athletes shouldn't be concerned if Yegorova tests negative because it would mean the drugs advantage would have worn off.

Gabriela Szabo though has decided to drop her threat of a boycott and attempt to add the 5,000 metre gold to the 1,500 she won on Tuesday night.