The Jamaican, who sealed an amazing third haul of three Olympic sprint gold medals in Rio, has consistently been a beacon for clean athletes amid doping and corruption scandals that mired Sebastian Coe's first year in office as IAAF president.
Bolt will compete at next year's world championships in London as his swansong, meaning the next Olympics in Tokyo will not feature one of sport's most recognisable figures.
"The man is a genius," Coe said. "There's been nobody since Muhammad Ali who's got remotely near to what this guy has done in terms of grabbing the public imagination."
However, Coe argued that just as a new generation of boxers emerged after Ali's retirement, so track and field would unearth new personalities after Bolt.
More From This Section
"It's a massive gap, but it's not a gap that is insuperable," Coe said.
"You're not going to fill that gap overnight, but there are great, talented athletes out there."
And Eaton was adamant that Bolt's absence would not leave a vacuum.
"I will say that it is an absolute pleasure to be able to compete in the same era as Usain Bolt," Eaton said.
"I really disagree he'll leave a vacuum.
"If anything, he's provided a platform for all the other young, aspiring athletes to launch from.
"Just now we're not seeing the fruits of his accomplishments and labour, but I think in the years to come you'll see a lot of young athletes who'll say 'I got inspired by Usain Bolt'.
==============================
Bolt will not be lost to the sport, however, with Coe saying he envisaged the Jamaican, so often able to deflect bad news with his on-track performances, playing a key role in years to come.
"I've been very clear, I said 'Whenever you decide to do other things, let's make sure in that portfolio of those things you will obviously want to go off and do, we don't lose you from the sport'," Coe continued.
"I'm very intent on that," he said, adding: "It's one of those discussions that probably you can in reality only have once someone's got their competitive years behind them.
Bolt himself said he thought the future of track "looked good".
"I want to stay around the sport. I want to stay in the sport," the 30-year-old said.
"The sport's being doing better, they're going to clean it up and it's going to do great."
Bolt's training partner Yohan Blake said it was up to the current wave of younger athletes to try to carry on the great man's track prowess.
"He is more than an immortal. He always encourages us to do better. We can push on after him and keep the legacy going."
"I hope I've set the bar high enough that no one can do it again," he said after the latest of his astonishing 20 Olympic and world titles.
"I'll have to make a new bucket list now, I've achieved all I wanted to in track and field.