Tsuboi ran second after taking over the #36 TOM’S GR Supra from teammate Yuhi Sekiguchi following a mid-race safety car period that shuffled the order, and was soon challenging the Rookie Racing car shared by Yamashita and Kazuya Oshima for the lead.
Yamashita held firm around the narrow, technical Okayama track as Tsuboi tried to make use of his superior speed through the sweeping Attwood right-hander leading on to the back straight to pass at the Turn 5 hairpin several times, but to no avail.
The long-running battle finally reached a resolution on lap 75 of 82 as Tsuboi attempted to brake late into Turn 5 and go all the way around the outside, only to lock up and run wide into the gravel.
Tsuboi didn’t lose any positions and sealed the runner-up spot just 1.1 seconds down on Yamashita following a late charge in the closing laps.
“While bearing in mind that two Supras shouldn’t collide, I tried to challenge without trying anything impossible. Therefore I had no choice but to go deep using the outside line [at Turn 5], and going off was the result of that.
“It’s frustrating and something I regret, but if I didn’t try, people would think, ‘this guy is someone who doesn’t attack’. I didn’t want to be thought of that way, so I clearly showed that I would try everything.
“If the third- and fourth-placed cars had been close and we would have lost a podium, so I shouldn’t have gone off, but it’s my job to push until the end.”
The 25-year-old, back in SUPER GT full-time after missing most of last year with his FIA World Endurance Championship commitments, admitted he felt bad for his rival Tsuboi but said he fully expected to be overtaken given his relative lack of pace.
“The Supra is always quick at Fuji and we only have 30kg of success weight, so if we fight tenaciously, we will have a chance. It’s also a long 500km race, so I want to win there.
“In any case, the fact that I was able to show such speed in a race without weights means that we have the performance to be a contender for the championship.”
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