PARIS • Usain Bolt's absence may feel like a giant void for fans, including International Association of Athletics Federations (IAAF) president Sebastian Coe, when the World Athletics Championships begin next month.
Bolt retired after the 2017 world meet, taking a haul of gold medals and jaw-dropping world records of 9.58sec in the 100m and 19.19sec in the 200m with him.
A star factor impossible to replicate, let alone replace, also left the sport.
"In my lifetime watching sport, I can't think of anybody other than Muhammad Ali that has had such an extraordinary global reach," Coe told The Associated Press in an interview on Sunday.
"Usain was what he was, not simply because he has a sack-load of medals and lots of world records. He was because he has a personality and that's the other thing we really make sure the athletes understand.
"Yes, they are in sport but their business is entertainment."
However, the head of athletics' governing body - who won Olympic golds in the 1,500m in 1980 and 1984 - hopes emerging young athletes make their own mark at the Sept 27-Oct 6 world meet in Doha.
"I don't think it's particularly healthy for a sport to rely on one person, however unbelievable the status is," the 62-year-old Englishman said in Paris - one day after a Diamond League meet.
"I take a lot of comfort from the prevailing group of athletes. I mean, Noah Lyles last night was a very good example (winning the 200m) in 19.65 seconds."
American Lyles, 22, is a strong contender to win gold in Doha, but his highly rated compatriot Christian Coleman may not be there.
Coleman, 23, faces allegations he missed three doping tests over a 12-month period. He has the year's leading 100m time with 9.81sec.
"My absorption of what he is saying is that he will be able to make a strong case as to whatever the issue is. I don't think there's much more I can add," Coe said.
In the wide-ranging interview, he also addressed issues like Caster Semenya's case.
Semenya will not be defending her 800m title in Doha after a Swiss court overturned a temporary ruling allowing her to compete without testosterone-suppressing drugs.
The South African, 28, is fighting the IAAF over rules requiring her to take the drugs to counter her naturally high testosterone levels.
She was born with a condition that results in male and female biological characteristics and testosterone higher than the typical female range.
"We made the judgment on what we felt was the best interest of the sport. It was probably inevitable there would be some challenges," said Coe.
"I don't think we were particularly surprised by that, and we remain confident that the regulations we have tabled are the right regulations."