Japan's Yuri Kano won the Nagoya International Women's Marathon Sunday and then set her sights on the world's top races including the 2012 London Olympics.

Kano crossed the line in 2hrs 27min 11sec ahead of Derartu Tulu of Ethiopia, who clocked 2:28:13, and compatriot Hiromi Ominami in 2:28:35. Japan's Mai Ito was fourth in 2:29:19.

The 31-year-old Kano, winner of the 2007 Hokkaido marathon, said she focused on winning the race, not on her time.

"With this victory, I think I can challenge in a better level of race in the world. Looking forward to the London Olympics, I want to strengthen my mentality to challenge on the world stage," she added.

The 2007 Rotterdam marathon champion Ominami, set to retire from the sport, led earlier in the race, upping the pace shortly before the 25km mark to reduce the 10-woman front-running group to five.

Japan's Yuko Machida lost pace shortly afterwards and Tulu, the Barcelona and Sydney Olympics 10,000m gold medallist, also slowed after the 27km mark.

"The top group was reduced quicker than I had expected," said Kano.

"When I tried to make a breakaway, it was a bit tough, but I felt good after I spurted. I tried to do what my competitors did in my previous defeats."