The result of a Handicap bet in tennis is calculated by adding up all games won per player and then applying the Handicap.
For example, if Player A beats player B 7-6 6-7 7-6, then Player A won 20 games and Player B won 19. A bet with a Handicap of -0.5 on Player A would win as 20 minus 0.5 is 19.5, which is more than 19.
Player A can win the match and still lose the -0.5 handicap. For instance, if Player A beats player B 7-6 2-6 7-6, then Player A won a total of 16 games and Player B won 18.
16 minus 0.5 is 15.5, which is less than 18, meaning a -0.5 Handicap bet on player A would lose.