A pic of Dire Tune (number 22) from another race

BOSTON, Massachusetts (AFP) - Kenya's Robert Cheruiyot won his fourth Boston Marathon crown in overwhelming fashion Monday while Ethiopian Dire Tune captured the closest duel in the race's history by just two seconds.

Cheruiyot's third consecutive victory in the 112-year-old race came in two hours, seven minutes and 46 seconds - 32 seconds shy of the course record he set in 2006 but still the sixth-fastest finish in Boston Marathon history.

"This was the most difficult," Cheruiyot said. "I wanted the race to be faster and better this year. I wanted to achieve my goal of 2:07 - not 2:08, 2:07. So that's what made it the most difficult. I tried to push harder."

In perfect conditions, the 29-year-old Kenyan grew tired with a slow early pace and pulled away, steadily outdistancing rivals until he spent much of the race alone and on record pace until slowing in the final mile.

"It is very difficult to run alone," he said. "You cannot run alone and meet 2:07. You need company to run a better race. The course is so tough, so it feels great to me."

Morocco's Abderrahime Bouramdane was second in 2:09:04 with compatriot Khalid El Boumlili third in 2:10:35 and Ethiopia's Gashaw Asfaw fourth in 2:10:47.

"When I decided to move I didn't look back," said Cheruiyot. "It's very difficult when I'm alone and Boston is not very good for (setting records). I wasn't worried. I didn't look behind. I just kept moving."

Cheruiyot's four titles, including 2003 and the past three years, are eclipsed only by Clarence DeMar's seven victories from 1911 to 1930, a time when fewer racers from outside North America competed in the event.

The victory likely secured Cheruiyot a spot on Kenya's Olympic team along with training partner Martin Lel, who eight days ago won the London Marathon in course-record time. No Olympic decision from Kenya is expected until June.

Tune won in 2:25:25, edging Russia's Alevtina Biktimirova in a two-woman duel over the final few miles that turned into a side-by-side battle down the last 400 meters.

Tune, 22, pulled ahead around the final turn with 600 meters remaining but Biktimirova, 25, answered to regain the edge before the African pulled ahead for good with 400 meters remaining.

"Even before I came to Boston, I was confident I could win," Tune said through an translator. "From the beginning to the end of the race, my training and performance helped me finish strong. I was certain I would finish first."

Tune became the youngest Boston winner since Joan Benoit at 21 in 1979.

Biktimirova, the 2007 Honolulu Marathon winner and sixth here in 2006, was second in 2:25:27 with Kenya's Rita Jeptoo third in 2:26:34, Latvia's Jelena Prokopcuka fourth in 2:28:12 and Ethiopian Askale Tafa Magarsa fifth in 2:29:48.

Jeptoo had won the previous tighest women's Boston Marathon finish by 10 seconds over Prokopcuka in 2006.

The men's and women's champions each received 150,000 dollars, twice the prize money for runner-up finishers, from a record purse of 796,000 dollars.

Former Tour de France champion Lance Armstrong was in the field of 25,310, the second-largest number of runners in Boston Marathon history to the 38,000 entrants for the centennial edition of the world's oldest annual marathon.

Armstrong finished his third career marathon, but first Boston effort, in 2:50:58.

"It was hard," Armstrong said. "I started well, started conservative, started on the slow side. I thought I would pick in up in the middle and then like everybody I started dying the last four or five miles.

"I love the challenge of the marathon. It's tougher than anything."

Armstrong said a return to the New York Marathon, where he set a personal best of 2:46:43 last year, was "on the schedule" for later this year and added that he looked forward to being back at the Boston race in 2009.