World record holder Kenenisa Bekele secured what he hopes will be the first leg of the long-distance double when he retained his Olympic 10,000 metres title with a devastating last lap.
After tracking the lead for most of the race, Bekele let rip over the last 400 metres to finish well clear of team mate Sileshi Sihine, who also got silver behind him in Athens, while Micah Kogo snatched bronze for Kenya.
Bekele's time of 27 minutes 1.17 seconds was an Olympic record, bettering the time he set in 2004.
With either Kenyans or Ethiopians dictating a brisk but not lethal pace, the lead pack slowly shed runners throughout the race. Only seven, including all three Kenyans and Ethiopians started the final two laps together.
The rapid closing speed was too much for Ethiopia's Haile Gebrselassie and his bid for a third gold after triumphs in 1996 and 2000 fell short as he fell back to sixth in the final 200 metres.
Gebrselassie, the marathon world record holder, has focused on the longer event in recent years but opted for the 10,000 in Beijing due to fears over air pollution
Bekele has said he hopes to race the 5,000 metres but would decide after Sunday's race.
East African runners took the top seven places in the race and only Eritrea's Zersenay Tadese, who finished fifth, managed to disrupt the Ethiopian-Kenyan duel.
"It was very difficult for me. I pushed the race very hard but he broke away and I didn't respond," bronze medallist Kogo told reporters.