Kenyan mutai holds flowers after winning the men's division of the 115th running .   Kenya's Geoffrey Mutai ran the fastest marathon in history to win the 115th Boston Marathon men's title on Monday while compatriot Caroline Kilel took the women's crown.
Mutai won in an official time of two hours, three minutes and two seconds to defeat countryman Moses Mosop by four seconds and beat the marathon world-record time of 2:03:59 run in 2008 at Berlin by Haile Gebrselassie of Ethiopia.
"I knew I could run well but the record was not on my mind," Mutai said. "I was feeling OK. I was confident in myself. I was training so much."
Mutai, 29, broke the Boston Marathon men's record set by Kenyan Robert Kiprono Cheruiyot last year of 2:05:52.
Elevation drop and point-to-point course layout differences from other marathons will preclude sanctioning of Mutai's time as a world record, but despite a tailwind it will rank as the best under any conditions.
"I prepared myself well in cross country," Mutai said. "But I was not having any ideas about the world record."

American Ryan Hall seized the early lead before a pack of 11 closed upon him just after the mid-point of the race and Ethiopia's Bekana Daba led another surge that dropped half of that dozen.
When Mutai issued another challenge over the final five miles, only Mosop could counter.
Mosop closed late but could not overtake Mutai, whose prior personal best was a 2:04:55 from a runner-up effort last year at Rotterdam.
"I knew him but I was confident," Mutai said. "I tried to push myself. The wind was blowing on all sides all over the course.
We were not facing the wind but it was coming from all around us."

Ethiopian Gebre Gebremariam, who won in New York last October in his marathon debut, was third in 2:04:53, five seconds ahead of Hall in fourth.
With the exception of 2001, when South Korea's Lee Bong-ju finished first, men from Kenya or Ethiopia have won every single Boston race since 1991.
Kilel won the women's race in an official time of 2:22:36, two seconds ahead of American Desiree Davila with Kenya's Sharon Cherop third in 2:22:42.
In a thrilling finish, Davila passed Kilel for the lead on the penultimate turn but fell behind the Kenyan again as the finish line came in sight.
Davila made a final surge to lead once more but Kilel answered with 200 meters to go and seized the lead for good, collapsing as she crossed the finish line.
"The last 400 I tried to sprint and then I came to sprint again the last 200 meters,' Kilel said.
Davila just missed becoming the first US woman to win at Boston since Lisa Larsen Weidenbach in 1985, saying she was disappointed at the outcome but thrilled at the effort.
"It was the most incredible experience in my running career," Davila said. "She did a little bit better than me out there. That was all I had. My legs were shot. That (late surge) was the last thing I had.
"I thought maybe if I could get to the line I could get her at the lean. but I had nothing left."

On a cool and breezy day, 26,964 runners from 90 nations ranging in age from 18 to 81 challenged the famed hills of the Boston suburbs for a total prize money purse of 806,000 dollars, with 150,000 dollars going to the men's and women's winners.
Wakako Tsuchida set a world record of 1:34:06 to win her fifth consecutive Boston women's wheelchair title and complete a wheelchair sweep for Japan, the first time since 2007 that competitors from the same nation took both crowns.
Tsuchida broke the old mark of American Jean Driscoll from the 1994 Boston Marathon by 16 seconds in defeating runner-up Shirley Reilly of the United States by 6:55.
Driscoll was at the finish line to congratulate Tsuchida.
Also hoping to provide inspiration for Japan in the wake of last month's earthquake and tsunami, Masazumi Soejima surged to the lead in the final 400 meters and won the men's wheelchair race in 1:18:50, edging runner-up Kurt Fearnley of Australia and nine-time winner Ernst Van Dyk of South Africa by one second.
"I tried really hard and that was my goal this year," Soejima said through a translator. "With everything that has happened at home, I really wanted to work hard and win this race again with Wakako."