Spectators at Sunday's London marathon will be able to identify the leading men's contenders through their different racing strips for the first time at a major athletics event.
Italy's Olympic champion Stefano Baldini will wear a yellow vest, defending champion Martin Lel of Kenya will be dressed in red and Ethiopian race favourite Haile Gebrselassie will run in blue.
If the trial proves a success the experiment will be extended to the other four meetings in the new world marathon major series and also to the women's events.
"We will see how it works," London marathon chief executive Nick Bitel told Reuters on Thursday. "But I am sure it will be a success.
"Imagine a horse race in which all the jockeys were all dressed in the same colour?"
Bitel said organisers of the Golden League track and field series had already tried unsuccessfully to introduce contrasting racing strips as part of their constant battle to attract attention to their leading athletes.
The London event has become the world leader among the big city marathons but no amount of organisation and money can prevent the perennial injury woes.
Sunday's race has lost its two world-record holders with Paul Tergat joining Paula Radcliffe on the sidelines this week after sustaining a calf injury.
Tergat and Gebrselassie staged a series of epic races over 10,000 metres throughout the 1990s, culminating at the 2000 Sydney Olympics when the Ethiopian just held off the Kenyan five-times world cross-country champion after a frenzied sprint finish.
"This is the most frustrated I have been in my career," Tergat told reporters. "I was calling this the race of the century. It's very rare to find the quality of athletes you find here.
"I had focused so much on this race, I had done everything possible to make sure I competed in a race like this."
The absence of Tergat and Radcliffe, who has a foot injury, is also a blow to the fledgling world marathon major series which started in Boston this month.
Organisers of the Boston, London, Berlin, Chicago and New York events have joined forces in a series which will culminate at the 2007 New York event with one million dollars prize money divided between the top men and women finishers.
Tergat's enforced absence on Sunday makes Gebreselassie the clear favourite and the little Ethiopian master seems to have timed his preparation to perfection.
After a persistent wind frustrated his attempt at a world record in Amsterdam late last year, he has set world marks this year over the half-marathon and 25 kms on the road and believes he has come to terms with his new event.
"I would bet on Haile," Tergat said. "He is a smart guy, he has learned a lot about tactics."
American record holder and Olympic bronze medallist Deena Kastor is favourite for the women's race in Radcliffe's absence.
"I've always been an aggressive runner and I'm going to run aggressively," she told a news conference on Thursday.
Temperatures on race day are forecast to range from eight to 18 degrees Celsius with 68 percent humidity, light rain and light southerly winds.