Three South Africans will look to hold their own on Thursday night after a fourth entrant, 400m hurdles specialist LJ van Zyl, withdrew on the eve of the Diamond League meeting in Oslo, Norway.
Van Zyl, out of sorts this season, said he had picked up a knee injury and would not race again for at least three weeks.
“I pulled out of the Oslo Diamond League due to a lingering knee irritation,” Van Zyl said in a statement on Wednesday.
“My coach, Hennie Kotze, has restructured my competition planning and training programme to allow myself time to rest for a few days.”
Van Zyl hoped to return to action at the continental championships at the end of the month.
“If everything goes according to plan, I will attempt to defend my African title at the African Championships in Benin between 27-30 June,” he said.
“We are confident that all measures are in place for a successful build-up to London Games.”
In his absence, fellow World Championships finalist Cornel Fredericks, who was included in South Africa's Olympic team on Wednesday, will lead a lone charge in the men's one-lap hurdles event in Oslo.
Fredericks lines up against a quality field which includes world champion David Greene of Great Britain and Javier Culson of Puerto Rico, the fastest man in the world this year.
Sprint sensation Simon Magakwe will again go in search of the Olympic qualifying standard of 10.18 seconds when he squares up against world record holder Usain Bolt and fellow Jamaican powerhouse Asafa Powell in the men's 100m event.
Magakwe consistently went under the qualifying mark during the domestic athletics season, but he must achieve the standard again at international level before the June 30 deadline to book his place in the SA team for the London Games.
Distance runner Elroy Gelant will also hope to dip under the qualifying mark of 13:20 in the men's 5 000m race.
Gelant must still achieve the standard twice to secure his place in the Olympic squad, but he will have a golden opportunity against a super line-up which includes world record holder Kenenisa Bekele and a host of Kenyan and Ethiopian stars. – Sapa