Boston ? The Kenyan national anthem got its annual airplay in the Back Bay on Monday after another Boston Marathon sweep.

It was the Americans, though, who were boasting of a breakthrough.

Robert Cheruiyot finished in 2 hours, 7 minutes, 14 seconds to nip the course record by a single second, and Rita Jeptoo won the women’s race for Kenya’s fourth sweep since 2000. With five American men in the top 10 – including Nos. 3, 4 and 5 – the United States had its best finish since the addition of prize money in 1986 helped bring back the top international fields.

“It’s exciting to see a lot of American guys run well,” said Olympic silver medalist Meb Keflezighi, who was third behind Cheruiyot and Kenya’s Benjamin Maiyo. “The crowd was just phenomenal. When they were chanting, ‘Go USA! Go Meb! Go USA!’ I was like, ‘I’m glad I’m here.”‘

Keflezighi, a naturalized citizen from Eritrea who lives in San Diego, ran with the leaders until the 16th mile and then began falling behind. Brian Sell, from Rochester, Mich., was fourth, catching Alan Culpepper around the last turn before the Copley Square finish.

“When Brian went by me, I thought he was some guy that jumped on the course,” Culpepper said, evoking memories of 1980 shortcut-taker Rosie Ruiz.

Culpepper, from Lafayette, Colo., was fourth last year, a performance that matched the best U.S. finish since 1987. The last American to win in Boston was Lisa Larsen-Weidenbach in 1985; no American man has won since Greg Meyer in 1983, and 12 times since then there have been no Americans in the top 10.

“For those of us who are in it and make our profession, we’re probably not as surprised as other people. We’ve seen this coming for a while. We’ve seen this building,” Culpepper said. “I think it is a new day, for sure.”

Cheruiyot and Jeptoo each claim an olive wreath, a bowl of beef stew and a $100,000 first prize. Kenyan men have won 14 of the last 16 Boston titles and its women have won three in a row and six of seven.

“I think we’d given in to the fact that the East Africans are supposed to dominate the race,” said Kevin Hanson, whose club in Rochester, Mich., trained seven of the top 22 men’s finishers.

“And we haven’t come up with a reason why.”

Cheruiyot let Maiyo set a blistering pace and ran off his shoulder before taking the lead.