The Potty-Mouthed, Baby-Faced Japanese Racer Who Became a Cult Star

The pressure was on Yuki Tsunoda. Within days, he would compete in a Formula 1 race in his home country, Japan. Bad luck had forced him out of two previous races minutes before the start, and speculation was rife that he might be demoted after some disappointing performances.

Yet at a fan event in central Tokyo last week, Mr. Tsunoda appeared jovial as he shared the stage with several rivals. When a moderator asked him to teach his fellow drivers a few words of the local language, Mr. Tsunoda took the microphone and chirped, “We are all slower than Yuki” in Japanese, drawing a laugh from the hundreds of fans hoisting their cellphones for photos.

It was in keeping with an impish persona, and, atypically for a top-level Japanese athlete, a foul mouth and devil-may-care attitude that has inspired a cult following and an international appeal that outstrip his accomplishments so far in F1.

When he made his debut in 2021, he was the youngest driver on the F1 grid and, as it happens, the shortest (he still is, at a reported 5 feet 3 inches). With his baby face, Mr. Tsunoda, 23, quickly gained an incongruous reputation for cursing volubly on the radio that drivers use to give feedback to engineers and mechanics — audio traffic that is also broadcast to fans during races.

Clips of him shouting “Shut up!” and other less printable outbursts went viral on social media, and his colorful reference to a “traffic paradise” that angered him on the track became a meme among fans.