Longman Dictionary of Contemporary English
game point
noun
EXAMPLES FROM CORPUS
▪ Even so she almost got away with it, and four times had game point.
▪ Still, it was Monami's six double-faults, three on game point, that really swung the match Javer's way.
▪ We play for about 40 minutes to a dead heat at game point.
Wiktionary
game point
n. (context tennis English) A situation where if one of the two players wins the next point, he or she will win the game (but not the set).