Sone triumphed in the women's over-78 kilograms division as the heavyweight classes brought to a close the individual judo competitions here.

The 21-year-old reigning world champion continued the domination of the host nation by defeating Cuba's Idalys Ortiz nearly nine minutes into the golden score period.

It was a low key ending as London 2012 gold medallist Ortiz, who already boasted an Olympic medal of every colour, forfeited the contest after collecting three shido penalties.

Two were for non-combativity and one was for a false attack, enough for a red card.

"There were times I hated judo," said Sone.

"But I'm happy I fought through it.

"Words cannot explain how tough the training has been, but that built my foundation."

Iryna Kindzerska of Azerbaijan and France's European champion Romane Dicko won bronze medals.

Krpalek won the men's under-100kg at Rio 2016 and won gold for the second Olympics in a row at the class above.

The world champion defeated Guram Tushishvili of Georgia with a side-locking hold against the tatami for ippon.

"When I won gold at Rio, it was a special moment for me and something precious," he said.

"In Rio, I said that I am going to do the 100-plus category to get a new motivation and try to achieve what I achieved in the under-100 category, to win the World Championships, European Championships and Olympic Games. 

"Those are very difficult steps to take. 

"I didn't really believe I could do it.

"It was a huge dream for me. 

"I didn't believe till the last moment, but I managed it, and I achieved it."

Krpalek takes over as heavyweight champion from France's Riner, who was bidding for a third Olympic title in a row.

The 10-time world champion was unseeded due to his infrequent appearances at competitions and the 32-year-old did not look at his best in the morning, eventually losing in the quarter-finals to world number one Tamerlan Bashaev of the ROC.

He recovered to win bronze alongside Bashaev, who fell in the semi-finals to 2018 world champion Tushishvili.

Riner also won Olympic bronze at Beijing 2008 before topping the podium at London 2012 and Rio 2016.

"I am over the moon," he said.

"It's been a day that went well. 

"I would have liked to end it differently, but I'm very proud of having managed to go all the way to win this bronze medal.

"I know, and I think everybody knows, that the Olympic Games is very difficult for everybody. 

"Maybe every athlete tries for one medal in a career. 

"Me, I have four medals, and I am very happy to come back with a fourth medal for my family, for my staff, for my team.

"Preparing for the Olympics was very difficult, very challenging with the pandemic and with the postponement of the Games. 

"In those few months I got injured.

"It's been an enriching experience, obviously, and I've learned a lot. 

"I think in sport, you learn a lot that you can bring to the rest of your life."

Riner will now compete for France in tomorrow's mixed team event, which will be held at the Olympics for the first time and will close the judo competition.

He could also continue towards a home Olympics in Paris in 2024.

"I have maybe two options again," he said.

"Tomorrow, maybe gold medal. 

"The next time is Paris 2024. 

"After, I close the book."