Robert Cheruiyot set a course record in the Boston Marathon on Monday as he and women's winner Rita Jeptoo pulled off a Kenyan sweep.

It was an outstanding day for the Americans, too.

U.S. runners Meb Keflezighi, Brian Sell and Alan Culpepper came in third, fourth and fifth, 23 years after the last American winner, Greg Meyer. Americans took five of the top 10 spots.

But Cheruiyot, the 2003 champion, pulled away for the best showing in Boston. His time of 2 hours, 7 minutes, 14 seconds was a second better than the winning time fellow Kenyan Cosmas Ndeti in 1994. Kenya's Benjamin Maiyo finished second, 1:06 off the pace.

In the women's race, Jeptoo pulled away with about 2 miles left, the sixth Kenyan woman to claim the title in seven years.

Last year's winners were Hailu Negussie of Ethiopia and Catherine Ndereba of Kenya.

Jeptoo's winning time was 2:23:38 in her marathon debut in the United States. She won marathons in Stockholm and Milan in 2004. Jelena Prokopcuka of Latvia finished second in 2:23:48 and Reiko Tosa of Japan was third in 2:24:11.

With 6 miles left in the women's race, which started 29 minutes before the men's, Tosa had fallen off the pace set by Prokopcuka and Jeptoo. But with 4 miles left the three were back together, running side-by-side along Commonwealth Avenue in Newton, just west of Boston.

Ndereba, who won her fourth Boston Marathon and second straight last year, wasn't in the field.

Cheruiyot had stayed off the pace for much of the race before running for a while with Maiyo, who led at the midpoint, then bolting in front. The remaining runners were far behind.

Kenyan men had won all 10 men's races between 1991 and 2000 and 13 of 14 before Negussie won last year. But Negussie fell behind early Monday and never challenged for the lead.

Maiyo was in a lead pack of three runners with Keflezighi and Deriba Merga of Ethiopia in his marathon debut. About four miles before the 13.1-mile midpoint, about 10 runners had been separated by 4 seconds on the coolest day for the Boston Marathon in four years with a starting temperature of 53 degrees and a crosswind of 4 mph.

For the sixth straight year, Ernst Van Dyk of South Africa won the wheelchair division, which began at 11:25 a.m. His time of 1 hour, 25 minutes, 29 seconds. Edith Hunkeler of Switzerland won the woman's wheelchair race in 1:43:41.

First prize for men and women is $100,000 each and, for the third straight year, they started at different times to give the women a cleaner and more visible race. The women started at 11:31 a.m. and the men's start was divided into two groups for the first time.

The 10,000 men with the fastest qualifying times began at the traditional noon start. The remaining men had a starting time a half hour later.

In 2004, Tosa won the Nagoya Marathon and finished fifth at the Olympics in Athens. Prokopcuka is a three-time Olympian, who was outstanding last season — finishing fourth in Boston and winning in Osaka and New York.

The official field of 22,517 entrants is the second largest in Boston Marathon history, representing 94 countries and all 50 states.

The race is the first in the World Marathon Majors competition starting this year that will award points to top runners based on their finish in five of the elite races: Boston, London, New York, Berlin and Chicago.

"Monday is the start of two races," New York City Marathon director Mary Wittenberg said. "One of the races will be over in 2 1/2 hours. The other race — to be the world's greatest marathoner — won't be over for 18 months."