Naohisa Takato earned his second straight gold medal and Funa Tonaki picked up a silver to boost Japan into an early lead at the World Judo Championships, which kicked off Thursday.

Takato successfully defended his men's under-60 kg weight class title and became a three-time world champion with a win against world No. 2 Robert Mshvidobadze of Russia.

"The match was getting away from me but I just couldn't accept that," the 25-year-old Takato said. "I'm glad because I thought I absolutely did not want to give up the red bib (worn by the defending champion)."

Takato beat world No. 1 Ryuju Nagayama in an all-Japan semifinal bout that rounded out Japan's three-medal haul on the opening day at National Gymnastics Arena.

Tonaki, ranked fourth in the world, was unable to defend her women's under-48 kg title and finished runner-up to world No. 3 Daria Bilodid of Ukraine.

"I'm beyond frustrated," Tonaki said. "Since I could only show a little of what I'm capable of, I want to show off my best next time."

The 23-year-old Tonaki defeated former world champion and current world No. 1 Monkhbatyn Urantsetseg in the semifinal. She beat Urantsetseg in last year's final in Budapest to claim her first world championship title.