Dear Jane,
It seems that you had(have) been unfair to your friends.Instead of get(getting) angry with him,you should have congratulated him his performance in the basketball match.You should go and speak to him as soon as possibly(possible) but(and) tell him you are sorry for reacting badly to losting(lose) the game.Tell to(去掉to) him you want to be his friend again.Basketball is only a game what(that) is played for a(去掉a) fun.Yes,it is good to win but it is far more important to enjoy playing.Sport should not make anger(angry) but should be about friendships.You should spare some time to have a talk with her(him).