Sebastian Coe considers Usain Bolt to be in the same sporting category as Muhammad Ali and said athletics will need "proper horsepower" to drive the sport when the legendary sprinter retires.
Bolt is set to end his phenomenal career after the World Championships this year and will go down as one of the greatest sportsmen of all time regardless of how he performs in London.
IAAF president Coe knows the Jamaican sprint king will leave a huge void in the sport and likens the impact he has made to that of the late, great boxer Ali.
Coe stressed the importance of ensuring there is no shortage of interest in athletics without Bolt.
"You'd be surprised if as IAAF president I was looking forward to this guy not racing. It's a high-class problem when you have an athlete like Usain Bolt in your sport." Coe said.
"Sparing his blushes, in my lifetime in sport I've not seen another athlete grab the sporting landscape since Muhammad Ali. I put them in the same category.
"The big challenge is to make sure when we don't have Usain out there to get people to recognise our sport is full of extraordinary talent both in track and in field.
"So there is more interest than ever in making sure that we put the proper horsepower behind helping the sport and not just our sport but understanding that actually, if you look at what we do, we are the mother of all sports."