Tsuboi was left to lament making his mandatory pitstop on lap 26 of 40 during Sunday's race, moments after long-time leader Yuhi Sekiguchi lost a wheel and triggered a safety car period.
The Inging Toyota driver was just leaving the pits as the safety car was called, and while he was initially happy to have jumped ahead of Tomoki Nojiri, it was the drivers that stayed out on track for one more lap that really benefitted from the intervention.
That meant Sasahara was easily able to complete his obligatory tyre change and resume at the head of the field, despite having been running behind Tsuboi prior to Sekiguchi's misfortune, with the Mugen driver going on to pull away and score his first Super Formula win.
"We had a chance to win and we wasted it, so it’s a pretty frustrating second place," commented a dejected Tsuboi post-race.
"At the time I came into the pits, we didn’t know there would be a safety car, but we saw on the monitors that Sekiguchi had stopped. When I pitted out, I could see the safety car boards at Turn 1, and I was just thinking about getting to the second safety car line.
"Finally I was able to get ahead [of Nojiri], so at the time I thought the safety car came at a great time. After that, I was wondering where the safety car was. I thought I was in the lead, I didn’t know the situation."
Tsuboi came into the 2022 season having been a constant presence near the top of the timesheets in pre-season testing, but up until Sunday's race he had only managed to score points once with eighth place in the Fuji season opener.
Admitting that without the second safety car he would have beaten long-time leader Sekiguchi, Tsuboi said he would try and at least take the positive of a first series podium finish since his Fuji win in 2020.
"This year we’ve shown some speed but we haven’t converted that into results for several races, so honestly it’s been painful," said Tsuboi. "But this time we were able to qualify on the front row and fight properly in the race.
"The result is a shame, but if there had been no safety car and if it had been a normal race, I don’t think we would have won either. Today we didn’t have the strength to win, so to finish second is positive.
"We finally showed some speed in dry conditions, and we solved some of the problems we had before, so now it feels like the season starts here.
"It’s frustrating, but there are a lot of positives. It’s hard to say which is the prevailing feeling, but at the very least, I’m happy to finish on the podium for the first time in two years."
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