Losing the game on a fault serve

Hi, Lets say my I am at game point (10), and my opponent is serving. If he makes a bad serve, do I win the game? He says that you can not lose on a serve if its game point. Is this true? I couldnt find such a rule. Thanks, J

Hi Jason,

That is not correct.  If he makes a bad serve on gamepoint then that is the end of the game.