Kenya have won all but one of the last nine men's London marathons, with 2010 being the odd year out when Ethiopia's Tsegaye Kebede beat Emmanuel Mutai by four seconds.
But after sweeping the 2011 race and taking the top two places last year, Kenya's marathon dominance in the city was broken on the biggest stage - the London Olympics.
Uganda's Stephen Kiprotich pulled off a shock win at the Games after accelerating away from Kipsang and Kenya's twice world champion Abel Kirui with six kms left.
Kipsang, who took the bronze medal, said he expected the leading Kenyans to run together until the pacemakers dropped out and then it would be down to whoever was fastest at the finish.
"I think we want to run as a team and try to run a faster time to maybe break the course record and see how far we can go faster," the 31-year-old told Reuters.
Kipsang missed out on the course record by four seconds when he won in a time of two hours four minutes 44 seconds last year.
The pacemakers have been instructed to run at 2:03:30 pace until 32 kms, although world record holder Patrick Makau was expecting a tactical race and did not think his mark of 2:03:38, set in Berlin in 2011, would be broken on Sunday.
"I can't talk about the world record," he said solemnly.
"The course is different from the one in Berlin and we have a very big group of athletes which are strong, so I can't say that the world record will be in danger," added Makau, who was one of the favourites last year but dropped out of the race with a hamstring problem after 16 kms.
As a consequence, Makau was not selected for the Kenyan Olympic team.
"That was something which disappointed me a lot although I can't say that it has affected my training. My training has been good," he said.
"It will be like a championship where we will be trying to run as Kenyans. We will be running like a team.
"This is the best chance for the Kenyans to see the best team which can be in the world championships (in August)," added Makau.
The Kenyan line up also includes 2011 London champion Emmanuel Mutai and Geoffrey Mutai, whose time of 2:03:02 when winning the Boston Marathon in 2011 is the quickest recorded for the 42.195 kms distance although it did not count as a world record because of the downhill course.
But in a field organisers are describing as the greatest assembled for a single race, the Kenyans may not have everything their own way. Uganda's Olympic champion Kiprotich and Ethiopia's Kebede, winner in Chicago last year, could be the men to foil them again.
Three times London champion Martin Lel of Kenya withdrew from the race this week with a hamstring injury, and Kirui pulled out with a stress fracture.
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