Ryouma! The Prince of Tennis Shinsei Movie: Tennis no Ouji-sama Ryoma! The Prince of Tennis
Provoked by his father—the legendary "Samurai Nanjirou" who won a US tennis championship—Ryoma is determined to train himself in the US after winning a championship in Japan. After running into his classmate Sakuno and getting in trouble with street gangs, Ryoma accepts a tennis match against the villains to save her.
Through the intense tennis battle, the shock of two colliding tennis balls somehow makes the stream of time leap.
Ryoma and Sakuno find themselves transported decades back to Ryoma's father's last match at a championship in the US.
[Source: GAGA Corporation; emended]