Nonetheless, the runner - who won a gold medal at the 2016 Olympics and has run a marathon in as little as 2:00:25 - maintains his status as the top marathoner in the world.
Olympic champion Kipchoge, who has the third-fastest personal best time of two hours, three minutes and five seconds, is keen to break the two-hour barrier and set a world record which now stands at two hours, two minutes, 57 seconds.
With two kilometres to run Kipchoge made his move and Adola had no response, leaving the 2015 victor to pull clear and take another impressive victory - his eighth in nine marathon starts.
Korir, who represented the East African country in 10,000m, said that the race will no doubt be the "Marathon of the Year" with a world record in the offing as three of the world's best road runners push themselves to the limit. Kipchoge was smiling, Adola wasn't.
The time is not an official world record due to some aspects to the event that led to the time not satisfying International Association of Athletics Federation (IAAF) criteria because it was run under a controlled environment.
Kipsang set the world record of 2:03:23 during the 2013 Berlin Marathon where a total of seven men's world records have been broken between 1998 and 2014.
Bekele has, typical of him, preferred to play his cards close to his chest, but remains confident he can run faster than the 2:03:03 personal best time he ran in winning last year's race ahead of Kipsang. Rainy conditions slowed the course, considered the fastest in the world.
The Kenyan finished in 2 hours, 3 minutes, 32 seconds, missing out on the world record by 35 seconds in wet conditions. That result was also in Berlin.
However, there were surprises as both former world record holder Wilson Kipsang and last year's victor Kenenisa Bekele dropped out after the halfway stage. Last year's champion, Kenenisa Bekele of Ethiopia, left the course soon after. He fell off the pace around 22K.
The next Abbott World Marathon Major is the Chicago Marathon on October 8.
The race starts at 10am, Kenyan time, and will be televised live on SuperSport 7 and 9 with a record 43,853 athletes from 137 countries entered to run and, hopefully, cross the Brandenburg Gate finish line.