Young football player had knee injury (think his name in the movie is Skylar). After that he ends in jail with father of a girl he stood up for prom. That man the night before while having dinner with his wife, daughter an her fiancé told his wife that he cheated on her. Now, because boys parents are on vacation and he doesn’t have place to live because his wife kicked him out of the house, he moves in into boys house and gradually start to help him recover and play again.
“Comeback Season” (2006)
The football star’s name in the film is Skylar Eckerman (played by actor Shaun Sipos).
Quote from IMDb:
“Walter Pearce (Liotta), a married man, tries to win back his wife (Headley) after cheating on her. Pearce enlists the help of the local high school football star (Sipos) to help him.”
I am pretty sure this is the movie you are looking for. If you agree, then please upvote my answer and select it as Best Answer, there are options for these.