By Helen Reid
LONDON (Reuters) -Kenya's Kelvin Kiptum set a London Marathon course record on Sunday, finishing in two hours, one minute, 25 seconds, nearly three minutes ahead of second-placed Geoffrey Kamworor in a rain-drenched race full of drama.
Kiptum, who ran the fastest-ever debut marathon in Valencia last year, made his break at mile 19, establishing a solid lead to deliver the second-fastest marathon of all time.
The 23-year-old collapsed on to the ground, exhausted, after crossing the finish line. He ran the second half of the race in just 59 minutes and 45 seconds.
"I am so happy with the result," Kiptum told the BBC. "I don't know what to say right now, I am just grateful."
Earlier, Dutch middle-distance athlete Sifan Hassan scored a stunning upset to win her debut marathon, an event she saw as a test which could pave the way to her competing over the marathon distance at next year's Paris Olympics.
Hassan, who has won Olympic gold in the 5,000 and 10,000 metres, made a dramatic comeback after an early injury to prevail over Olympic champion Peres Jepchirchir and defending London champion Yelamzerf Yehualaw in what organisers said was the best ever elite women's field for the event.
The 30-year-old looked to be in pain around the hip flexor just under an hour in, falling behind as she stopped and stretched, but she caught up with the leading pack with just over six kms to go.
Hassan finished in 2:18:34 with a desperate sprint in the final 100 metres, three seconds ahead of second-placed Alemu Megertu of Ethiopia. Kenya's Jepchirchir finished third.
"I learned to be patient and just to run your own race," Hassan told a news conference. "Just keep going as much as possible and maybe you will surprise yourself."
Hassan said she planned to run the marathon in either Chicago or New York later this year after focusing on the track for the World Athletics Championships in Budapest in August.
The women's marathon world-record holder, Kenya's Brigid Kosgei, was a surprise early drop-out, limping off the course less than three minutes into the race. She has been battling a hamstring injury.
In his last marathon before retirement, Britain's Mo Farah finished ninth in 2:10:28.
Switzerland's Marcel Hug won the elite men's wheelchair race, beating his own course record with a time of 1:23:44 for his third London victory in a row. Australia's Madison de Rozario clinched the women's wheelchair race in 1:38:51, in a thrillingly tight win over Switzerland's Manuela Schaer.