Sho Tsuboi ended a Super Formula victory drought dating back to 2020 with a first win of the season for TOM’S in Sunday’s fourth round at Fuji Speedway.
Tsuboi had started from fourth and slipped to fifth on the opening lap, but showed overwhelming race pace to claw his way back into contention and eventually beat Toshiki Oyu by a commanding margin of 7.1 seconds.
Leaving his mandatory pit stop late, Tsuboi cycled to the front as early leader and polesitter Nirei Fukuzumi pitted on lap 14 of 41 and second-placed Oyu did so on lap 17.
Tsuboi waited until lap 28 to make his stop, coming out behind not only Oyu but also early stoppers Tomoki Nojiri and Tadasuke Makino, as a slow pit stop from the KCMG crew meant Fukuzumi slid down the order.
But Tsuboi was immediately on the attack with the benefit of fresher tyres, passing Makino and Nojiri in quick succession at the end of lap 30 and then closing down race leader Oyu at a rate of over one second a lap after that.
What appeared to be an inevitable pass for the lead came on the run down to Turn 3 as Tsuboi slipped ahead of Oyu’s Inging machine before the braking zone.
Tsuboi’s victory marked his first since joining TOM’S from Inging at the start of this season and his third in total, and came on the same day his wife Aimi Saito triumphed in the supporting all-female Kyojo Cup race.
Oyu held on for second, clinching his first podium since leaving Honda to join Toyota this year, while Nojiri completed the podium for Team Mugen.
Nojiri’s team-mate and nearest title rival Ayumu Iwasa endured a disastrous race, bogging down from second on the grid to drop down to 13th on the opening lap.
The Red Bull junior elected to leave his pit stop until almost the last moment possible in case of a safety car, but a caution never materialised and he finished out of the points in 11th.
Watch: Round 4: Fuji Highlights
It means Nojiri has stretched his championship lead out to 9.5 points at the mid-point of the season, with Tsuboi now his nearest rival in second.
Fukuzumi fought his way back ahead of Makino in the closing stages to salvage fourth, having taken KCMG’s first-ever Super Formula pole position on Saturday.
Fifth for Dandelion Racing’s Makino has moved him ahead of Iwasa into third place in the drivers’ standings, 14 points behind Nojiri.
Yuji Kunimoto scored Team Impul’s best result of the season so far in sixth place ahead of Nakajima Racing’s Ren Sato and Kamui Kobayashi in the second KCMG car.
Completing the top 10 were Impul substitute Hibiki Taira, who scored his first-ever points in Super Formula, and Naoki Yamamoto for Nakajima Racing.
Sena Sakaguchi was an early retirement, his Inging machine grinding to a halt on the opening lap, while Kakunoshin Ota in the second Dandelion car was a non-starter after suffering terminal problems on the grid.