The lingering threat of COVID-19 at the rescheduled Tokyo Olympics has not disappeared for athletes, who are faced with a series of rigorous testing and quarantine measures before being allowed to compete.
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Not only will athletes be tested daily, but temperature checks will be required upon every entry to the Olympic Village. Those with a positive result will be isolated in a ward and the fate of their competition will be determined by the Results Advisory Expert Group (RAEG).
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Whilst this summer's Olympic Games may be logistically different due to the pandemic, it will also see the sporting event going ahead without some of its most prestigious athletes.
From Coco Gauff's positive COVID test to Michael Phelps' unexpected retirement, HELLO! takes a look at the biggest stars who won't be competing in the Tokyo 2020 Olympic Games.
Sports stars who won't be competing in the Tokyo 2020 Olympic Games
The most prominent star to have ended his Olympic career is the legendary Usain Bolt. His dazzling athletics career was sadly struck short after he suffered a hamstring injury in the last 50 meters of the 4x100m at the 2017 world championships.
The 11-time World champion is widely considered 'one of the greatest sprinters of all time', but the Jamaican star retired before he could compete in the 2020 Olympics.
Roger Federer will not be playing tennis at the Tokyo Olympics after suffering from a "setback" with his knee.
Taking to Twitter, the eight-time Wimbledon champion said: "I unfortunately experienced a setback with my knee, and have accepted that I must withdraw from the Tokyo Olympic Games."
"I am greatly disappointed, as it has been an honour and highlight of my career each time I have represented Switzerland. I have already begun rehabilitation in the hopes of returning to the tour later this summer," he continued.
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At the last Olympic Games in 2016, US swimming champion Michael Phelps confirmed on the TODAY show that he would be hanging up his goggles for good.
"This time I mean it," he insisted, after being initially lured out of retirement so he could compete in the Rio games.
The American swimmer currently holds the record for the most Olympics medals won by any athlete, including 23 gold medals and 13 individual golds, despite only being 28 years old.
Four-time Olympic gold medalist Serena Williams announced that she will not be taking part in the rescheduled Olympic games. During a pre-Wimbledon press conference, the star told reporters: "I'm actually not on the Olympic list—not that I'm aware of. If so, then I shouldn't be on it."
Her decision to withdraw from the games comes after strict COVID-19 rules mean Japan has barred athletes from travelling with their families, as well as international spectators from watching the games. Earlier this year, Serena indicated that she would not attend the Olympics if it meant being separated from her three-year-old daughter (and budding tennis pro), Olympia Ohanian.
The star told NBC: "I haven't spent 24 hours without her, so that kind of answers the question itself."
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Sir Bradley Wiggins is regarded as one of Team GB's most legendary athletes, yet announced his retirement from cycling after 16-year career in December last year.
The professional won the Tour de France and a record eight Olympic medals during his time, including being part of the four-man team pursuit side that won gold at the Rio Olympic Games that summer.
After the devastating news that her COVID-19 test was confirmed positive, the American tennis star was forced to withdraw her place from the Tokyo 2020 Olympic Games. Despite not having won any Olympic medals, the talented 17-year-old was coined one of the front runners after her performance at Wimbledon this summer.
"It has always been a dream of mine to represent the USA at the Olympics and I hope there will be many more chances for me to make this come true in the future," said the American tennis player.
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