London 2012 gold medal winner Greg Rutherford feels "so incredibly sorry for all the athletes" who will be competing behind closed doors at Tokyo 2020.
The Tokyo Games, which get under way on July 23, having been delayed 12 months due to the coronavirus pandemic, will take place without spectators as the Japanese capital remains in a state of emergency.
Rutherford, who was roared on by his home crowd when he leapt to long jump gold nine years ago and will be in Tokyo as one of Eurosport's team of presenters, told the PA news agency: "It will have a massive effect. I feel so incredibly sorry for all the athletes.
"They're going to miss out on the thing that is my fondest memory of competing at an Olympic Games.
"At London 2012 in particular, having an entire crowd behind me and giving me that support genuinely helped me win the gold medal.
"I feel really sorry for the Japanese athletes. It's their once-in-a-lifetime opportunity to have their home Games. They're not going to experience what I did."
The 34-year-old won gold at London 2012 on 'Super Saturday' alongside track and field team-mates Sir Mo Farah and Dame Jessica Ennis-Hill, with all three crowned Olympic champions within an hour of each other.
"When you're in a stadium and everybody is getting behind you, it's so unbelievably special," he said. "It's out of this world, to feed off the crowd's energy and these athletes are not going to have that at all.
"Equally, there will be athletes who 100 per cent hate the big crowd and actually this is the perfect scenario for them.
"But generally, we'll see people performing to the best of their capability, but sadly they won't be able to revel in that moment."
Rutherford will team up with fellow London 2012 gold medal winners Sir Bradley Wiggins and Joanna Rowsell as 'roving' reporters as part of Eurosport's Tokyo 2020 coverage.
The sports broadcaster, whose parent channel Discovery was in 2015 awarded the European television rights for the Olympic Games until 2024, has unveiled innovative plans to attract a younger audience, using the latest digital technology.
Eurosport's UK coverage will be broadcast from its state-of-the-art studio in West London, The Cube, via presenters Orla Chennaoui, Reshmin Chowdhury and Radzi Chinyanganya.
Rutherford, who will be covering athletics, swimming and diving, added: "The Cube itself is an absolutely fascinating piece of technology.
"It's going to add something really special to what we're doing in Tokyo. I just can't wait to get out on the ground and be involved.
"Because of Covid, we're not going to be bouncing off each other, we're not going to be as close to the athletes.
"It's about trying to create that Olympic experience, maybe outside the stadium where we can do catch-ups, talking to the athletes and getting some of the behind-the-scenes stuff as well."
