Why Kobayashi started on wet tyre in dry Super Formula decider

Kobayashi headed into the finale with an outside shot at the title, trailing pre-race leader Naoki Yamamoto by 10 points with 13 on offer for winning the race.

Starting down in 16th position, Kobayashi pitted at the end of the first lap to switch from the wet tyres to softs - getting around the rule that requires drivers to use both dry-weather compounds in a race, including the slower medium.

However, a race free of safety car periods meant that Kobayashi never had the chance to make up the ground he lost at the start.

KCMG boss Tsugio Matsuda, a two-time Formula Nippon champion and current Nissan Super GT driver, said the unconventional strategy was the only way Kobayashi stood a chance of winning the race.

"To be honest, it was a strategy I didn't want to do," Matsuda told Autosport. "But the chance of becoming champion remained, and it was the only way to win the race.

"Scoring a few points wouldn't have been enough to win the title.

"If the safety car had appeared before lap seven, Kobayashi would have taken the lead.

"There was no choice other than that to get on top. But the safety car never came.

"In the first race of the season [also held at Suzuka], there were four safety car periods. This time there were none."

Kobayashi's strategic options were further limited by a new rule ahead of the Suzuka weekend that dictated drivers must use both tyre compounds within the pit window, which for the season finale opened on lap seven.

"It was OK," said Kobayashi of his opening lap. "I just drove following the [other] guys. But I expected more than where we finished.

"In the end, it was quite bad luck we didn't get a safety car. Anyway, with that [grid] position, without a safety car, we had no chance.

"The times we led [this season], there was a safety car and we didn't win, and when we hoped for a safety car, there wasn't one. It was always the opposite [of what we wanted]."

Kobayashi was on track to finish 10th with his strategy, but he ran out of fuel in the dying stages and slipped to 12th behind Sho Tsuboi and Lucas Auer at the finish.

The Toyota LMP1 regular admitted KCMG had gone aggressive on fuel and needed a safety car period to be certain of making it to the end.

"We just lost a few seconds [after running dry] but when you have a safety car it's much easier [to save fuel]," he explained. "I tried to lift a lot, but not enough."

Nick Cassidy would eventually seal the 2019 Super Formula title ahead of Yamamoto and Alex Palou, who suffered a nightmare season finale.