A hamstring injury has forced world marathon record holder Paul Tergat to pull out of the BUPA Great South Run.
Tergat pulled out four days before the Great North Run
The problem had already led to the 36-year-old Kenyan withdrawing from the Great North Run 11 days ago.
Tergat is still not 100% fit and does not want to jeopardise his major target this autumn, the New York City Marathon on Sunday 6 November.
"It is regrettable but understandable," said Matthew Turnbull, the Great South Run's elite athletics director.
"With the New York marathon coming up, understandably he is concentrating on being in the best shape he can be for that."
Turnbull is now searching for a replacement runner for the country's biggest 10-mile race on Sunday, 9 October.
It has already attracted Ethiopia's former Olympic and world marathon champion Gezahegne Abera.
The Ethiopian will be joined by Spain's number one Juan Carlos de la Ossa, who earlier this year smashed his national 10km record at the Great Caledonian Run in Edinburgh.
The women's race features two-times Olympic 10,000m champion Derartu Tulu, Sonia O'Sullivan of Ireland and Abera's wife Elfenesh Alemu, fourth in last summer's Olympic marathon.