The Kenyan will take on Uganda's surprise Olympic champion Stephen Kiprotich, world champion Abel Kirui, fellow Kenyan and Berlin marathon winner Geoffrey Mutai and three-time London winner Martin Lel.
"It's a very strong field with about 10 guys who have run sub 2:05:15. So if they can run freely in a way where there is no fearing one another, I think the record is very possible," Kipsang told Reuters in Iten, a small town 2,400 metres above sea level in western Kenya's Rift Valley.
Kipsang missed the London course record by four seconds when winning last year's race and his marathon best of 2:03.42, set in 2011 in Frankfurt, is four seconds short of Patrick Makau's world record.
"I came very close to breaking the world record. When I see Patrick I always joke with him: 'was it three or four seconds?'," Kipsang laughs, folding his thumb to show four and then three fingers.
Kipsang raced Makau over 42.1km for the first and only time in last year's London marathon but the world record holder limped out after 16km.
The duo will renew their rivalry around the streets of the capital with Kipsang citing the 27-year-old as one of the two biggest obstacles to the defence of his London title.
However, he sees close friend Mutai as the biggest threat.
The 32-year-old clocked the fastest marathon ever in a time of 2:03:02 in Boston in 2011, but the record was not ratified because of the brisk tailwind and because Boston is considered too much of a downhill course.
"We have not met in marathon before but Geoffrey's speed, especially from 30km to 35km, is really good," Kipsang said, minutes after having lunch with Mutai in the garden of his newly opened hotel Keellu, which stands for 'goodluck' in Swahili.
"I don't know how this year will turn out but I think those two are the biggest rivals."
Among the Ethiopians bidding to ensure their east African neighbours do not have it all their own way will be Tsegaye Kebede, who won the 2012 Chicago marathon and the 2010 London race, Ayele Abshero, who won last year's Dubai marathon in the sixth-fastest time ever (2:04.23) and Feyisa Lilesa, another sub-2:05 man.
"A lot will depend on how you feel on the day of the competition," said Kipsang, while pointing out there is little separating the top runners.
On first sight, Kipsang's polished black shoes, smart trousers and neatly pressed shirt would suggest he's just another hotel manager. But the respect and warm embraces afforded to him by the guests highlight his high standing in Iten.
The 30-year-old said this position as the role model to youngsters in the area was now fuelling his ambition - both on track and in his business dealings.
"I enjoy being a role model. I saw putting up a hotel like Keellu as one way of giving back to the community. Yes, it is an investment but it also employs lots of people and helps those who grow food in the area," Kipsang said.
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