Mo Farah has swerved the challenge of competing in a second successive London Marathon which will be illuminated by a first meeting between world record holder Dennis Kimetto and two-time race winner Wilson Kipsang.
Farah, who finished a disappointing eighth on his marathon debut in the English capital last year, will instead concentrate on preparing to defend his 5,000m and 10,000m titles on the track at the World Athletics Championships in Beijing in August.
The 31-year-old endured a torrid season last year, collapsing after the New York Half Marathon prior to his appearance in London, before illness forced his withdrawal from the Commonwealth Games in Glasgow.
The double Olympic champion from London 2012 has already been forced to pull out of the Great Edinburgh Cross Country international challenge this weekend after suffering from flu over the Christmas period, which affected his preparation for the start of the year.
In the build-up to last year's London Marathon, Farah refused to confirm his participation for the 2015 event but his decision is likely to have been swayed as much by his commitments this year as his performance in front of record crowds last April.
Paula Radcliffe, two-time London Marathon winner and world record holder, told IBTimes UK last May: "Without a doubt he is the best in the world right now at 5,000m and 10,000m and he will soon be right up there with marathon runners, although he is not the best yet.
"He knows he can go faster and his preparation [in training] wasn't ideal going into London [last] year but your first one is rarely your fastest one."
The absence of Farah will be offset by the news that Kimetto, the world record holder after running two hours, three minutes and 23 seconds in Berlin will face the man he usurped as the world's fastest marathon runner Kipsang, for the first time in London.
"I broke Wilson's world record in Berlin last year and now I want his London Marathon crown," Kimetto said. "I am relishing the chance to face my friend over the famous course. I know it won't be easy but I am confident I can go the distance whatever he throws at me."
Emmanuel Mutai, the 2011 winner, will also be in action meaning the three fastest marathon runners of all time will compete among the most star-studded line-ups in the 35-year history of the elite men's race at the London showcase.
The glittering list also includes Ethiopian track champion Kenenisa Bekele and British runner Steve Way, who competed at the Commonwealth Games for England.