The 26-year-old Mutai won the 42.2-kilometer (26.2-mile) race for the first time, clocking 2 hours, 4 minutes, 40 seconds for the fourth fastest time for a marathon.

Mutai broke away at the 21-mile mark, and shattered Olympic champion Sammy Wanjiru's old course record of 2:05:10 from 2009.

“My dreams have come true because I had in my mind that of the five major marathons if I won one my achievement would have been greater,” Mutai said. “My aim was to win the race, not to focus on the time ... I tried my best to push it until the end. It is fantastic because I created two achievements - I won the race and I improved my personal best.”

Three-time champion Martin Lel was second in 2:05:45 after beating Patrick Makau in a sprint in front of Buckingham Palace. Having been troubled by hip and leg injuries, it was Lel's first London Marathon since winning his third title in 2008. He only received an invitation to compete after a knee injury forced Wanjiru to withdraw.

“After two years away it was important for me to have a good race here,” Lel said. “When (Mutai) left me, I wanted to go with him and I tried but he was too good for me today. I am happy with the second place because I am building up my race fitness again.” Mutai and Keitany emulated the Kenyan double in London from 2004, with Keitany becoming the fourth women's winner from the east African nation.

Like Mutai, the 29-year-old Keitany ran the fourth fastest marathon by a woman by finishing her London debut in 2:19:19.

After breaking away after the 15-mile mark, she was almost a minute ahead of defending champion Liliya Shobukhova, who ran a personal best of 2:20:15.

Keitany's fellow Kenyan Edna Kiplagat, who was also competing in the English capital for the first time Sunday, finished third with a personal best 2:20:46.

Keitany was almost 10 minutes faster than her third-place performance in New York last November.

“I surprised myself because before I knew I was with the winner of London last year and the one from New York (Kiplagat),” Keitany said. “I was a bit scared at first, but then we continued moving I believed in myself that I would make this. I feel very happy.”