V - Egao no Tame ni

Come spring, Nishiwaki Haruka becomes a second year high school student. For a second time. Due to accidents and illnesses, she didn't have enough attendance, thus the repeat year. She transferred to Yamabuki High to run away from her old friends. One day, the baseball team from her old high school came for a friendly match, and Haruka bumped into some old friends. Her new classmate, Ono Kenta, found out her secret. She agreed to be the manager-cum-player to their weakling baseball team in order to keep him from telling her secret...
(Source: Manga Updates)