The world No 4 from Switzerland trailed 5-2 in the tiebreak but raised his game to close out the match in straight sets at a renovated Bercy Hall.
"I was not in a good position, that's for sure," Wawrinka, who is bidding to become the first player to win the French Open and the Paris Masters in the same year since Andre Agassi in 1999, told a news conference.