Yamashita and his teammate aboard the #14 Toyota GR Supra, Kazuya Oshima, salvaged a third-place finish from 11th on the grid in Sunday's Motegi finale, giving them a first podium finish since their victory at Okayama in April.
The five Bridgestone-equipped Toyotas occupied the bottom five positions in a miserable qualifying session for the GR Supra contingent, and Yamashita and Oshima were eliminated from title contention by failing to score pole.
Come the race however, Oshima was able to climb to fifth in the opening stint, helped by numerous cars ahead hitting trouble, before the #14 crew gained two more places in the pitstop phase.
Yamashita was then able to keep pace with the two leading cars, the Team Kunimitsu Honda and Impul Nissan, in his stint, while also holding off a late charge from the recovering NDDP Racing Nissan to clinch third.
"We tried a new set-up direction which worked well, and although we weren’t fast enough to pass the top two cars, we were able to keep up with them," Yamashita told Motorsport.com's Japanese edition. "So considering the situation after qualifying it was quite a good race.
"If this set-up works at other tracks, I feel like we could be fast in the race anywhere, but we won’t actually know that until we go to those places.
"Qualifying and the race are two separate things, and it feels like we had a bad set-up for qualifying. For the race we worked hard and found a different set-up direction. But if you asked me if we would have a better qualifying with this set-up, I don’t think we would have."
Third place meant that Yamashita and Oshima crucially finished the year as the top Toyota duo in the standings in fifth, beating TOM'S duo Sacha Fenestraz and Ritomo Miyata by six points in the final reckoning.
Yamashita had previously said that this would be the team's goal as it would mean getting priority for new parts in 2023.
"We finished as top Toyota crew, and we had a final race that could prove useful for next season, so although it was a tough season I feel like we did what we could," he said. "I think we achieved the minimum result."
Fenestraz bemoans "terrible" farewell weekend
The #37 TOM'S machine of Fenestraz and Miyata recovered from 14th on the grid to finish sixth in a race that the pair had to win in order to stand any chance of becoming SUPER GT's youngest-ever champions.
Fenestraz, who will leave SUPER GT next year after signing to race in Formula E with Nissan, said that the #37 crew had followed Bridgestone's recommendation in terms of tyre selection for the Motegi weekend, only to soon realise that they had made the wrong decision.
"It was a terrible weekend for us, not what we expected for the last race," Fenestraz told Motorsport.com. "After free practice we realised that we and all the Toyotas had chosen along with Bridgestone the wrong tyres for the weekend.
"It’s a shame, but it shows how important having the right tyre choice is in this championship. Without that, you don’t have any chance. It happened too many times this year to allow us to fight for the championship.
"We managed to save it with P6 in the last race, but I don’t think there was any room to do better."
