Defending champions Desisa, Rotich lead Boston Marathon field

Defending champion Lelisa Desisa can expect a strong challenge from a bevy of top runners on Monday as he seeks his third Boston Marathon victory in four years.

Ethiopia's Desisa has built an impressive marathon resume with three victories in nine starts at the distance.

That includes triumphs in Boston last year and in 2013 -- when the event was marred by the explosion of two homemade bombs that killed three people and injured 264 others among the crowd at the finish line.

"Everyone comes here to win but with God's help I will win again. My training has been better than it was last year," Desisa, who won last year in 2hr 9min 17sec, said on Friday.

But the men's field looks wide open, with 2012 winner Wesley Korir, now balancing his duties as a member of Kenya's parliament with his training, among the challengers.

"I've run here four times, and I think this is a very strong (field)," Korir said. "There's not really a clear favorite as there used to be, so you'll find people running as a group to the end."

Last year's runner-up, Ethiopian Yemane Tsegay, will be looking to improve on that performance and add a major marathon victory to his resume after proving himself with wins at the distance in Ottawa, Daegu, Eindhoven and Taipei.

Kenyan Sammy Kitwara, runner-up in Chicago last year, is also searching for a first major marathon crown. While he has thrived on the flat Chicago course he's tackling Boston for the first time and it remains to be seen how he'll cope over the hilly Boston terrain.

- Rotich also under pressure -

Kenya's Caroline Rotich also faces stiff opposition in her repeat bid.

Ethiopian Tiki Gelana the London Olympics gold medallist and Olympic record-holder hasn't shown the brilliance of 2012 in the last couple of years.

But she has the added motivation of knowing Ethiopian as well as Kenyan selectors are taking Boston results into consideration in choosing the team for the Rio de Janeiro Games, and a strong performance could give her a chance to defend her Olympic crown.

Rotich ran a tactically outstanding race last year, timing her final push perfectly 100 meters from the line to beat Ethiopian Mare Dibaba, with Ethiopian Buzunesh Deba third.

?I have concluded that it was one of my best races," Rotich said.

- Security enhanced -

Boston marked the third anniversary of the marathon bombings on Friday. With that somber observance in mind and in light of attacks since then in Paris, San Bernardino and Brussels, security remains at the forefront.

The FBI said there was so far no credible threat to the marathon, but investigators remain on alert for anything that could develop into one.

A drone ban will be in effect and the National Nuclear Security Administration has been using a low-flying helicopter to measure baseline levels of radiation along the race route.

David Procopio, a spokesman for the Massachusetts State Police, said the highly visible contingent of uniformed personnel along the route will be joined by plainclothes officers, but officials don't want the security to be overwhelming.

"We don't want to create an environment akin to an armed camp or a military base," he said.