Norwegian siblings Henrik, Filip and Jakob Ingebrigtsen said on Tuesday that they will act as pace setters when Kenyan Eliud Kipchoge tries again to break two hours for a marathon, in Vienna on October 12.
Olympic champion and world record holder Kipchoge has already had one tilt at a sub two-hour time at the Monza race track in May 2017.
On that occasion the 34-year-old was just 25 seconds off the mark in a specially-prepared race using a pacemaker vehicle, as well as runners positioned to shield him in a bid to cut wind resistance.
The assistance meant his time could not be validated by the IAAF. That will also be the case in Vienna. The world record, which the Kenyan set in Berlin last year, is 2hr 01min 39sec.
Henrik Ingebritsen, 28, won gold in the 2012 European championships over 1,500m. His brother, Filip, 26, earned a bronze over the same distance in the 2017 worlds. At 18, Jakob, is already double European champion having taken gold last year in both the 1,500m and 5,000m in Berlin.
"This won't be a competition for us - we shall just be assistants," Filip told NRK broadcaster.
"A lot of things have to work in order to beat the record and you have to be on a good day.
"He went close last time and he has since improved on his personal best so if he is in the same form as Berlin, I'm expecting a record," he added.
Kipchoge also won this year's London marathon and has only failed to win once over the distance - finishing second to compatriot Wilson Kipsang in the Berlin marathon in 2013.