Yamauchi claimed victory in a course record time of 69min 17sec.

The 36-year-old gradually pulled in the American Deena Kastor - who had at one stage built up a lead of 200 metres - with two miles of the race remaining.

The Japanese-based runner, who missed much of last season including the World Championships in August with a foot injury after finishing second in London, only returned to racing in February.

"I'm still not back at my very best but I'm getting there," said Yamauchi, who succeeds compatriot Paula Radcliffe as champion.

"When Deena went away, I thought if I could make the top three that would be okay.

"When she came back in sight I thought: 'Wait a minute, this race isn't over."'

Kastor finished in 69:43 with Madai Perez of Mexico just two seconds behind the 2004 Olympic marathon bronze-medallist.

The American will return to her New Mexico base for a final few weeks high altitude training before competing in London.

Ethiopia's double Olympic champion Haile Gebrselassie failed to finish the men's race after suffering an asthma attack.

Peter Kamais of Kenya, 33, claimed victory in 59:52c ahead of countryman Moses Kigen-Kipkosgei who clocked 1:00:38 with Mohammed Trafeh of the United States third in 1:00:40.


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