Former marathon world record holder Haile Gebrselassie has given up on his dream of competing in London 2012.
The Ethiopian, who turns 39 on Wednesday, was a two-time Olympic 10,000m champion before switching to the 26-mile distance in 2004.
But he has been unable to win a place in Ethiopia's Olympic marathon team.
"Many Ethiopian athletes run 2:04 and Haile cannot run that any more. He has given up on the Olympics with pain in his heart," said manager Jos Hermans.
The athlete suffered a setback in his bid to qualify for London 2012 by finishing fourth in February's Tokyo Marathon with a time of 2:08.17.
Eighteen of his compatriots have clocked faster marathon times this year, which left the veteran with an uphill battle to earn his place.
Gebrselassie insists he will continue to run long distance and has confirmed his participation in May's 10k Great Manchester Run, which he has won in each of the last three years.
"Although I will not be taking part in the Olympic marathon I am still enjoying my athletics career and looking forward to coming to Manchester again and to a course which I love," he said.
But Gebrselassie, who also won four World 10,000m titles, admits he plans to run his final competitive track race over the middle distance in the Netherlands next month.
"This will be my last 10,000 metres race," he said. "But I still feel good. There is only a small difference compared to 2011. I am just a bit slower now."
Last weekend he beat Britain's Paula Radcliffe in a head-to-head half marathon, dubbed the "Emperor versus the Queen" race, in Vienna.
Gebrselassie, who gave a head start of seven minutes 52 seconds to Radcliffe in the 13.1 mile race, finished in 1:00.52.
Haile Gebrselassie's medal haul
1993 World Championships: Gold (10,000m), Silver (5,000m)
1995 World Championships: Gold (10,000m)
1996 Olympic Games: Gold (10,000m)
1997 World Championships: Gold (10,000m)
1999 World Championships: Gold (10,000m)
2000 Olympic Games: Gold (10,000m)
2001 World Championships: Bronze (10,000m)
2003 World Championships: Silver (10,000m)
