Ethiopian legend Haile Gebrselassie announced his retirement on Sunday, after dropping out of the New York City Marathon with a knee injury.
The 37-year-old - a two-time Olympic champion at 10,000 metres - said that he would devote himself to other matters.
“I never think about to retire. But for the first time, this is the day,” he said. “Let me stop and do other work after this.”
Gebrselassie, nursing an inflamed right knee, pulled out of the race at the 16-mile mark.
The marathon world record-holder, who is involved in numerous business ventures in his homeland, had treatment on his knee before the race and pulled up with a wince of pain on the downhill of the Queensboro Bridge.
He had run 16 miles in 1 hour 19 minutes 40 seconds.
Gebrselassie, the 1996 and 2000 Olympic 10,000m champion, has won the Berlin Marathon four times and triumphed at Dubai the past three years.
He set the world marathon record of 2:3.59 in 2008 at Berlin.
While he had voiced pleasure at a chance to compete in New York for the first time, he acknowledged via Twitter before the start of the race and in a pre-race television interview that he had some inflammation in his knee.
“I have some inflammation in my right knee, because of the long travel to NY city,” he wrote on the micro-blogging site. “No big problem, just some fluids. Hopefully the knee holds!”
Marathon officials said Gebrselassie had an MRI on Saturday that found fluid and tendinitis in the knee.
Since the 2008 Beijing Olympics, where he didn’t run the marathon for fear the city smog would aggravate his asthma, Gebrselassie has said he saw no reason he couldn’t run in the 2012 London Games.
He won his fourth Berlin Marathon title in September of 2009 - skipping that race this year as he focused on New York.
In May he won his third Great Manchester Run in England, although as he had in Berlin 2009 Gebrselassie admitted after the race that he found the going difficult.
“I don’t want to complain anymore after this, which means it’s better to stop here,” Gebrselassie said on Sunday.
Comments