The official marathon world record appears likely to come under threat next month after Eliud Kipchoge, Wilson Kipsang and Kenenisa Bekele were all confirmed in the field of the Berlin Marathon.
Olympic champion Kipchoge is considered the leading contender to beat the time of two hours, two minutes and 57 seconds recorded in Berlin by fellow Kenyan Dennis Kimetto three years ago.
Kipchoge set an unofficial world record for the 26.2-mile distance in May, clocking two hours and 25 seconds in Nike's 'Breaking2' challenge at Monza. His time did not count for official purposes because of pacing and hydration rules.
While the 32-year-old will arguably be the favourite on September 24, compatriot Kipsang and Ethiopian distance-running great Bekele can be expected to offer a stiff challenge.
The personal bests of the trio are all within 16 seconds of Kimetto's world record and all three have previously won in Berlin. Kipsang triumphed in 2013, registering what was then a world record time of 2:03.23, while Kipchoge and Bekele won in 2015 and 2016 respectively.
"It's a dream match-up," said race director Mark Milde. "It's not often that the three strongest marathon men in the world race each other. As organisers we are crossing our fingers for good weather and thrilling competition."