Ethiopia's Olympic champion Kenenisa Bekele ran well within himself to retain his world 10,000 metres title on Monday and then said he would not double up in the 5,000.
After cruising in the middle of the pack for the first half of the race, Bekele surged to the front on the final lap and then kicked in the last 200 metres to outsprint compatriot Sileshi Sihine for victory in 27 minutes 8.33 seconds.
The pair finished in the same positions at last year's Athens Olympics.
The 23-year-old Bekele had also been entered for the 5,000, which starts with a preliminary round on Thursday, but says he will not double up.
"I will not run the 5,000," Bekele told reporters.
"It's been a very difficult year for me since the death of my fiancee. Also I don't think I can run three different races at this championship."
Bekele's season was sadly interrupted when his 18-year-old fiancee suddenly died during a training run in January. After a period of mourning he recorded his fourth successive double at the world cross country championships a few weeks later.
Kenya's Moses Mosop won the bronze on Monday to spoil what was expected to be Ethiopia's second sweep of the championships after their women had dominated the 10,000 final.
Abebe Dinkesa Negera, who with Sihine had taken turns up front during the race, faded to seventh, while the fourth Ethiopian, Gebre-egziabher Gebremariam, never really featured.
Bekele never looked troubled on a track soaked by the day's heavy rain but said he had found the going hard.
"It was a very hard race because of the rain and we (the Ethiopian runners) weren't able to work together as much as we would have liked. I'm happy we got two medals," he added.
Bekele attempted the 10,000 and 5,000 double at the 2003 world championships and last year's Athens Olympics.
He won the 10,000 at both events but failed to add the 5,000 titles, finishing third in Paris in 2003 and second at the Olympics.
The feat has never been achieved at the world championships and was last done at the Olympics in 1980.
The final of the 5,000 metres takes place on Sunday.
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