Teenager Yuma Kagiyama produced two exquisite quadruple jumps to lead the way in the ISU Grand Prix of Figure Skating NHK Trophy men's singles after the short program, as he recovered from an earlier error on his axel.
The 17-year-old perfected his quadruple Salchow-triple toe loop and quadruple toe loop jumps to receive high execution scores from the judges, leaving him with a total of 87.26 points.
But despite topping the standings, the Lausanne 2020 Winter Youth Olympic Games champion was left disappointed with a popped triple-axel, for which he scored no points.
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"I was really, really frustrated with myself," Kagiyama said afterwards about his mistake.
"The first half of the programme was better than anything I had done in training - a Salchow-toeloop included - and I thought this was going to be good.
"I started thinking too much, trying to perfect it and couldn't move the way I wanted to.
"I thought I was close to perfect on the quads and I'm pleased about that because they were better than anything I was doing in practice."
Kazuki Tomono placed second on 83.27 points in the men's short program, while Lucas Tsuyoshi Honda rounded off the podium in third on 79.22 points.
In the women's event Kaori Sakamoto ended the day in the lead after a dazzling performance in Osaka, as the 20-year-old pulled off a triple Lutz for the first time in her competitive career.
Sakamoto's combination of double axel, triple Lutz and triple flip-triple toe loop earned her a competition-best score of 75.60 points, with Wakaba Higuchi finishing second on 69.71 points, and Mako Yamashita on 67.56 points in third.
Finally in the mixed ice dancing event, Tim Koleto and Misato Komatsubara finished top of the pile with a score of 70.76 in Osaka, as the Japanese champions continue to amaze on the ice with another scintillating performance.
Vancouver 2010 Winter Olympic bronze medallist and 2010 world champion Daisuke Takahashi was making his debut in the event, coming in second with partner Kana Muramoto, while Rikako Fukase and Eichu Cho finished the event in third.
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