The current top long-distance runners will clash in Germany's capital on Sunday with a trio, spearheaded by Olympic champion Eliud Kipchoge, threatening the world record at the Berlin Marathon.
Kenya's Kipchoge, 32, and Wilson Kipsang, 35, take on Ethiopia's Kenenisa Bekele, 35, in an elite lineup with former record-holder Patrick Makau and 2007 world champion Luke Kibet also in the mix.
Kipchoge is the man to beat in Berlin, where the current world record of 2:02:57 was set by his compatriot Dennis Kimetto in 2014.
Kipchoge has won seven of the last eight marathons he has entered, including the Olympic title in Rio when he finished a minute ahead of the field.
Kipsang, who ran a then-world record 2:03:23 in 2013 in Berlin, has announced that he plans to go under 2:02:20 in this year's race, but Kipchoge is just as determined to claim a new record.
"I won't decide until the last moment how fast I will start out, but I can say this: I want the world record," he said.
"Winning is not an option, it's a necessity," Kipchoge said. "I have grown mentally since I won in Berlin in 2015."
The world marathon record has fallen seven times in Berlin over the last 20 years.
The early autumn weather normally means little wind and ideal temperatures on a flat, fast course.
Alongside Kipchoge and Kipsang, who won the Tokyo marathon in February, is the Berlin marathon's defending champion Bekele, who came within six seconds of the world record in Berlin last year.
Bekele did so despite muscle cramps during the second half of the race to hold off Kipsang and this year promises a rematch alongside Kipchoge's considerable challenge.
"I expect a stiff competition from the two guys. All three of us are at the top of our game right now, but there will be only one winner," Kipchoge said earlier this month.
Kipchoge has already smashed the world record once this year - albeit unofficially.
In May, he came within 25 seconds of running the first sub two-hour marathon during a sponsored event at the Formula One race track in Monza, Italy.
The race was not recognized by the world governing body International Association of Athletics Federations, but now he wants the official record.
"It showed me what the human body is capable of and how we can push our limits if we can break the mental barriers," added Kipchoge. "I ran a pace of 2:50 per kilometer for almost two hours."
As for Bekele, he is targeting "a personal best of under 2:03:00."
Kipsang meanwhile has the record books in his sights.
"I want to go down in history as one of the runners to break the marathon world record twice. The last time that happened was nine years ago by Haile Gebrselassie."