In the ice dance free dance, while Komatsubara and Koleto – the most experienced of the three teams taking part – were favourites, a lot of attention was on the pairing of Muramoto Kana and Takahashi Daisuke, taking part in their first international competition together.
Takahashi, an Olympic medallist in singles, only switched to ice dance with Muramoto at the start of this year, but they looked settled and elegant through the first half of their free dance.
However, an error from Takahashi on the second set of twizzles, tripping over and having to put his hands on the ice to regain balance, proved insurmountable for the team.
While they scored well for their presentation and program components for an elegant dance set to the ballet La Bayadère, the deduction in technical elements placed them behind Fukase Rikako and Cho Eichu for both the free dance and overall.
"We made some errors that we normally wouldn't make. We felt like we were calm but maybe the nerves got to us," Muramoto said to media afterwards. "We now know how we stack up against the others. We have to take our programme up a level for the nationals and that's something we need to discuss. After the nationals we have Beijing (2022) in our sights."
Takahashi added: "In training, I don't usually trip up the way I did but things happen in a live competition. You have to have control of your emotions in situations like that.
"When I competed in the singles, I tried to stay light by controlling my diet. But now I'm eating a lot more, trying to add weight and strength for the lifts. I eat differently, train differently and I'm starting to get the hang of ligting. But I'm not comfortable yet. It's definitely an area I need to work on."
Komatsubara and Koleto, meanwhile, emphasised their status as the strongest ice dance team in Japan ahead of next month's national championships in Nagano.
Despite an error resulting in a deduction for them too, the husband-and-wife team (179.05) finished more than 21 points clear of Fukase and Cho (157.89).
It was Komatsubara and Koleto's first Grand Prix win.
"I never expected to win the NHK as a Japanese citizen up until now so this is an absolute honour among the other skaters," the American-born Koleto said.
"From here until the nationals we continue in the same way."
Ladies: Sakamoto unstoppable
Earlier, Sakamoto was simply flawless as she claimed her first career Grand Prix victory in the ladies' singles.
The 20-year-old, who twice won silver medals at Skate America, received positive execution scores from the judges on all of her elements, and was the only skater of 12 to receive a program component score above 70.
Skating to the Matrix soundtrack, the 2018 Four Continents champion was unstoppable on the day both technically and artistically, scoring in the nines for four of the five program components (and an 8.90 for her other).
Of particular note were Sakamoto's triple flip-triple toeloop combination and her triple loop. Not a single jumping element was marked down, and the Kobe skater knew she had done something special when she ended her routine.
Taking in a standing ovation from the crowd, Sakamoto had a giant grin on her face which continued into the kiss and cry. Upon seeing her scores, she let out a big squeal of joy and fist-pumped the air.
Sakamoto's free skate score of 153.91 gave her an overall total of 229.51 points.
"I was so nervous I could only think about the choreography," Sakamoto told media afterwards. "The best thing today was that everything went like it did in practice.
"If I didn't drop a few points in the short program on my spins and steps I could have topped 230 (points). At the nationals, I hope I can produce a perfect performance.
"I was nervous throughout the entire skate, down to the final spin. I found out today that I perform better when I'm nervous.
"It's unusual for me to be this nervous in a competition. Maybe it's because I didn't have much time after the six minutes (warmup). But I soaked up the tension well, I think."
Despite a number of errors in her free skate, Higuchi Wakaba finished second overall thanks to her short program score.
While Higuchi's free skate was pleasing to the eye artistically, she struggled on her jumps, popping two triples – a Salchow and a Lutz – down to doubles, while also getting called for a quarter under-rotation on a triple toeloop and an unclear edge on a triple flip.
Higuchi also attempted a triple Axel to open her program, the first time she had attempted it in international competition. However, it was called for a quarter under-rotation and received a negative execution grade from the judges.
Her final score was 131.27 – good for only fourth in the free – for a total of 200.98.
The new Japanese junior champion, Matsuike Rino, showed that she can challenge the best in Japan with her bronze medal.
Despite stepping out of a triple loop and twice being called for unclear edges on her triple flips, she had strong jumping elements including a beautiful triple Salchow-triple toeloop to finish.
She placed second in the free skate segment (133.23 points) behind Sakamoto, and had a total score of 198.97.
Lausanne 2020 Youth Olympic champion You Young of South Korea, the lone skater taking part in any of the three events at the NHK Trophy not representing Japan, recovered from her disastrous short program to finish seventh overall.
While it was by no means a clean free skate, with three jumps marked under-rotated, You looked to have loosened the pressure on herself after admitting she had felt nervous during the short program.
She appeared relieved after completing the skate, smiling and looking happier than she did yesterday.
"I think I was more comfortable because I did really bad yesterday. I think it helped that I wasn't as nervous as yesterday; it felt more like practice," You said.
"I'm happy I was at this competition because maybe the Worlds could be cancelled and this would be my only chance to perform in another country. It's my first time competing in Japan so it's a big meaning for me."