Tokyo 2020 Olympics - Open Water Swimming - Men's 10km - Final - Odaiba Marine Park - Tokyo, Japan - August 5, 2021. Oussama Mellouli of Tunisia swims past bottles of water offered to competitors during the race. REUTERS/Antonio Bronic 

Tokyo 2020 Olympics - Open Water Swimming - Men's 10km - Final - Odaiba Marine Park - Tokyo, Japan - August 5, 2021. Mario Sanzullo of Italy and Oussama Mellouli of Tunisia in action. REUTERS/Leonhard Foeger 

Tokyo 2020 Olympics - Open Water Swimming - Men's 10km - Final - Odaiba Marine Park - Tokyo, Japan - August 5, 2021. Oussama Mellouli of Tunisia in action. REUTERS/Leonhard Foeger 

Oussama Mellouli of Tunisia competes in the men's 800m freestyle heats during the World Swimming Championships at the Sant Jordi arena in Barcelona July 30, 2013. REUTERS/Albert Gea (SPAIN - Tags: SPORT SWIMMING)

Second placed Thomas Peter Lurz of Germany, winner Spyridon Gianniotis of Greece and third placed Oussama Mellouli of Tunisia (L-R) hold their medals during the men's 10km open water victory ceremony at the World Swimming Championships at De La Fusta venue in Barcelona July 22, 2013. REUTERS/Albert Gea (SPAIN - Tags: SPORT SWIMMING)

Spyridon Gianniotis of Greece (R) celebrates as he won the men's 10km open water race in front of second placed Thomas Peter Lurz of Germany (C) and third placed Oussama Mellouli of Tunisia (L) during the World Swimming Championships at De La Fusta venue in Barcelona July 22, 2013. REUTERS/Albert Gea (SPAIN - Tags: SPORT SWIMMING)

Spyridon Gianniotis of Greece (R) celebrates as he won the men's 10km open water race in front of second placed Thomas Peter Lurz of Germany (L) and third placed Oussama Mellouli of Tunisia (C) during the World Swimming Championships at De La Fusta venue in Barcelona July 22, 2013. REUTERS/Albert Gea (SPAIN - Tags: SPORT SWIMMING)

Second placed Eric Hedlin of Canada, winner Oussama Mellouli of Tunisia and third placed Thomas Peter Lurz of Germany (L-R) hold their medals after the men's 5km open water race at the World Swimming Championships in Barcelona July 20, 2013. REUTERS/Albert Gea (SPAIN - Tags: SPORT SWIMMING)

Winner Oussama Mellouli of Tunisia holds his gold medal after the men's 5km open water race at the World Swimming Championships in Barcelona July 20, 2013. REUTERS/Albert Gea (SPAIN - Tags: SPORT SWIMMING)

Winner Oussama Mellouli of Tunisia holds his gold medal after the men's 5km open water race at the World Swimming Championships in Barcelona July 20, 2013. REUTERS/Albert Gea (SPAIN - Tags: SPORT SWIMMING)

Third placed Thomas Peter Lurz of Germany, second placed Eric Hedlin of Canada and winner Oussama Mellouli of Tunisia (L-R) finish the men's 5km open water race at the World Swimming Championships in Barcelona July 20, 2013. REUTERS/Albert Gea (SPAIN - Tags: SPORT SWIMMING)

Oussama Mellouli of Tunisia (bottom) competes during the men's 5km open water race at the World Swimming Championships in Barcelona July 20, 2013. REUTERS/Albert Gea (SPAIN - Tags: SPORT SWIMMING)

Oussama Mellouli of Tunisia celebrates as he won the men's 5km open water race at the World Swimming Championships in Barcelona July 20, 2013. REUTERS/Albert Gea (SPAIN - Tags: SPORT SWIMMING)

Oussama Mellouli of Tunisia celebrates as he won the men's 5km open water race at the World Swimming Championships in Barcelona July 20, 2013. REUTERS/Albert Gea (SPAIN - Tags: SPORT SWIMMING)

Oussama Mellouli of Tunisia celebrates as he won the men's 5km open water race at the World Swimming Championships in Barcelona July 20, 2013. REUTERS/Albert Gea (SPAIN - Tags: SPORT SWIMMING)

Tunisia's gold medallist Oussama Mellouli, Germany's silver medalist Thomas Lurz (L) and Canada's bronze medallist Richard Weinberger pose after the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Dominic Ebenbichler (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's gold medallist Oussama Mellouli, Germany's silver medalist Thomas Lurz (L) and Canada's bronze medallist Richard Weinberger pose after the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Dominic Ebenbichler (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's Oussama Mellouli poses with his gold medal wrapped in national flag after the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Dominic Ebenbichler (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's gold medallist Oussama Mellouli reacts after the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Dominic Ebenbichler (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's gold medallist Oussama Mellouli reacts after the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Dominic Ebenbichler (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's Oussama Mellouli poses with his gold medal after the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Dominic Ebenbichler (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's Oussama Mellouli poses with his gold medal after the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Dominic Ebenbichler (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's gold medallist Oussama Mellouli reacts after the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Dominic Ebenbichler (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's gold medallist Oussama Mellouli salutes after the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Dominic Ebenbichler (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's gold medallist Oussama Mellouli listens to anthem after the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Dominic Ebenbichler (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's Oussama Mellouli kisses his gold medal after the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Dominic Ebenbichler (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's Oussama Mellouli poses with his gold medal after the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Dominic Ebenbichler (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's Oussama Mellouli celebrates after winning gold in the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Stefan Wermuth (BRITAIN - Tags: OLYMPICS SPORT SWIMMING TPX IMAGES OF THE DAY)

Tunisia's Oussama Mellouli celebrates after winning gold in the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. Pictured behind is Canada's Richard Weinberger. REUTERS/Stefan Wermuth (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's Oussama Mellouli celebrates after winning gold in the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Stefan Wermuth (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's Oussama Mellouli prays after winning gold in the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Stefan Wermuth (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's Oussama Mellouli prays after winning gold in the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Stefan Wermuth (BRITAIN - Tags: OLYMPICS SPORT SWIMMING TPX IMAGES OF THE DAY)

Tunisia's Oussama Mellouli prays after winning gold in the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Stefan Wermuth (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's Oussama Mellouli relaxes after winning gold in the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Stefan Wermuth (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's Oussama Mellouli celebrates after winning gold in the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Stefan Wermuth (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's Oussama Mellouli reacts after winning gold in the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Stefan Wermuth (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's Oussama Mellouli reacts after winning gold in the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Dominic Ebenbichler (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's Oussama Mellouli prays after winning gold in the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Dominic Ebenbichler (BRITAIN - Tags: OLYMPICS SPORT SWIMMING TPX IMAGES OF THE DAY)

Tunisia's Oussama Mellouli prays after winning gold in the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Dominic Ebenbichler (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's Oussama Mellouli reacts after winning gold in the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Dominic Ebenbichler (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's Oussama Mellouli relaxes after winning gold in the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Dominic Ebenbichler (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's Oussama Mellouli relaxes after winning gold in the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Dominic Ebenbichler (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's Oussama Mellouli competes to win gold in the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Dominic Ebenbichler (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's Oussama Mellouli competes to win gold in the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Dominic Ebenbichler (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Canada's Richard Weinberger (L) and Tunisia's Oussama Mellouli compete in the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Stefan Wermuth (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's Oussama Mellouli competes in the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Stefan Wermuth (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's Oussama Mellouli (L) competes in the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Dominic Ebenbichler (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's Oussama Mellouli prepares for the men's 10km marathon swimming at Hyde Park during the London Olympic Games August 10, 2012. REUTERS/Dominic Ebenbichler (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's Oussama Mellouli kisses his bronze medal on the podium during the men's 1500m freestyle victory ceremony at the London 2012 Olympic Games at the Aquatics Centre August 4, 2012. REUTERS/Jorge Silva (BRITAIN - Tags: SPORT SWIMMING OLYMPICS)

Tunisia's Oussama Mellouli poses with his bronze medal on the podium during the men's 1500m freestyle victory ceremony at the London 2012 Olympic Games at the Aquatics Centre August 4, 2012. REUTERS/Jorge Silva (BRITAIN - Tags: SPORT SWIMMING OLYMPICS)

Tunisia's Oussama Mellouli competes on his way to win bronze in the men's 1500m freestyle final during the London 2012 Olympic Games at the Aquatics Centre August 4, 2012. REUTERS/Toby Melville (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Tunisia's Oussama Mellouli holds his bronze medal during the men's 1500m freestyle victory ceremony at the London 2012 Olympic Games at the Aquatics Centre August 4, 2012. REUTERS/Brian Snyder (BRITAIN - Tags: SPORT OLYMPICS SPORT SWIMMING)

Gold medallist Sun Yang of China poses with silver medallist Ryan Cochrane (L) of Canada and bronze medallist Oussama Mellouli (R) of Tunisia on the podium during the men's 1500m freestyle victory ceremony at the London 2012 Olympic Games at the Aquatics Centre August 4, 2012. REUTERS/Jorge Silva (BRITAIN - Tags: SPORT SWIMMING OLYMPICS)

Tunisia's Oussama Mellouli swims to a second place finish during heat 4 of the men's 1500m freestyle event at the London 2012 Olympic Games at the Aquatics Centre August 3, 2012. REUTERS/Toby Melville (BRITAIN - Tags: OLYMPICS SPORT SWIMMING)

Oussama Mellouli of Tunisia swims in the men's 1500m freestyle heats during the London 2012 Olympic Games at the Aquatics Centre August 3, 2012. REUTERS/Tim Wimborne (BRITAIN - Tags: SPORT SWIMMING SPORT OLYMPICS)

Oussama Mellouli of Tunisia prepares to compete in the men's 1500m freestyle event during the USA Swimming Grand Prix Charlotte UltraSwim at the Mecklenburg County Aquatic Center in Charlotte, North Carolina May 13, 2012. REUTERS/Davis Turner (UNITED STATES - Tags: SPORT SWIMMING) 

Oussama Mellouli of Tunisia gestures after winning the men's 1500m freestyle final at the Arab Games in Doha December 22, 2011. REUTERS/Fadi Al-Assaad (QATAR - Tags: SPORT SWIMMING) 

Oussama Mellouli of Tunisia competes in the men's 1500m freestyle final at the Arab Games in Doha December 22, 2011. REUTERS/Fadi Al-Assaad (QATAR - Tags: SPORT SWIMMING) 

Oussama Mellouli of Tunisia competes in the men's 1500m freestyle final at the Arab Games in Doha December 22, 2011. REUTERS/Fadi Al-Assaad (QATAR - Tags: SPORT SWIMMING)