Sasahara was a last-minute addition to the Team Mugen set-up for this season, having initially looked set to miss out on a permanent seat within the Honda stable for a second season in a row.
Starting his year with a pole position at Fuji, the 26-year-old went on to score his first win at the same track in July, and added a second triumph in the opening race of last weekend's Suzuka double-header finale.
A difficult final race after contact with Sho Tsuboi left him sixth in the drivers' standings, while his contribution also ensured Mugen was able to secure the teams' championship for the first time in its history with a race to spare.
However, Sasahara's future remains up in the air as Mugen prepares to go back to operating the Red Bull-sponsored car in 2023.
This will likely entail running a driver of the energy drink giant's choosing alongside reigning champion Tomoki Nojiri.
Sasahara says that whatever happens at Mugen next year, he feels he deserves a spot somewhere on the Honda roster.
"Saturday’s race was like a dream, and it shows what I am capable of in Super Formula," he told Motorsport.com.
"I won two races this season, same as Nojiri and [Ryo] Hirakawa, and I was P3 among the Honda drivers [behind Nojiri and Tadasuke Makino]. I showed I deserve this seat, and I helped Mugen for the teams’ title.
"We built the #15 car at the end of February, there was no time at all [before the first pre-season test in March], all the crew was in their first season, and we showed what we can do. I’m really happy with how it went.
"If there is no reward, if there is no seat for me next year, I don’t understand."
Sasahara's chief engineer for this season, Tomo Koike, expressed his hope that Mugen can somehow find a way to keep his driver on board, although such an outcome would most likely depend on the team expanding to a third car.
"Ukyo is really fast, but there are some things that Honda doesn’t recognise about him," Koike told Motorsport.com. "So as a team we worked hard this year so that Honda would recognise his ability.
"We don’t know if he has a seat next year, but everyone wants to continue working with him, and we all gave everything to try and keep him in the team."
Koike was also keen to highlight how Sasahara helped Nojiri out of a set-up rut in the opening round of the season at Fuji, where the eventual champion could only qualify sixth while his teammate took a surprise pole.
"Ukyo was on pole for the opening race, and at that time Nojiri’s set-up wasn’t very good, so he was able to copy some elements of Ukyo’s set-up and he improved," explained Koike. "Because the tyre [construction] changed from last year, we had to use totally different set-ups from last year.
"But we worked well as a two-car team, which was down to the combination of both drivers, along with the engineers and mechanics."
