Osaka:Kenya's Catherine Ndereba kept the crowd involved right to the end of the marathon.
Ndereba sat behind frontrunner Reiko Tosa most of the way until surging into the lead at the 40-kilometer mark on Sunday, quashing Japan's best chance of gold at the track and field championships.
"This was one of the toughest marathons I've ever run because of the weather," said Ndereba, the 2003 world champion and 2005 silver medalist. "I was amazed to see so many runners left after 39 kilometers."
Ndereba crossed in 2 hours, 30 minutes and 37 seconds, with No 1-ranked Zhou Chunxiu of China eight seconds behind for silver and Tosa a further 10 seconds back to collect Japan's first medal of the meet.
As with the men's marathon a week ago, the women had to contend with some stifling heat. The temperature reached 31 C with humidity at 52 per cent as the leaders approached the finish.
The race started at 7 am local time to avoid the heat and Ndereba spent the first half of the race in a group of runners behind the leaders, conserving energy for a late charge.
When it became a group of eight at the 32-kilometer mark, Ndereba was right there along with compatriot Rita Jeptoo Sitienei, Tosa and Zhou.
Tosa, a silver medalist at Edmonton in 2001, bravely led from the front for the bulk of the race until Sitienei broke away with four kilometers to go, taking Ndereba and two Chinese with her.
"As I expected, it all came down to the last five kilometers," said Tosa, who had the nation's expectations to carry with her. "That's when the race was decided and that's when I started pushing for a medal."
Zhou and Ndereba traded the lead as Sitienei faded, and Tosa rallied to regain third spot from China's Zhu Xiaolin.
"The heat was a huge factor," said Zhou, already looking ahead next year's Olympics on home turf. "Ndereba finished ahead of me this time, but hopefully when we meet again in Beijing I'll be ahead of her."
Russia's Galina Bogomolova, who was in the leading pack at the start of the race, collapsed after the midway point and was one of 10 runners who didn't finish the race.
After getting vocal support from thousands who lined the course on Osaka streets, Tosa entered the stadium for the final 300 meters to loud and sustained applause. But Ndereba had built too big of a gap.
"After 40 kilometers, I was able to break away and maintain the pace until the finish line," said Ndereba, comparing it with her first world title. "This was a lot tougher than Paris."
Still, it was courageous effort by Tosa to give Japan what likely will be its only medal of the championships.
The nine-day competition concludes later on Sunday with seven other finals, and host Japan has no realistic chance of winning any.