The 19-year-old American built a 4-2 lead in the second set before a lengthy back-and-forth with chair umpire Pierre Bacchi. Gauff complained to Bacchi that he called her serve at deuce out only after Pliskova returned it into the net. Gauff had to repeat her first serve and went on to hold for a 5-2 lead. The U.S. Open champion said the argument “fueled” her.