Former champion Iga Swiatek kicked off her US Open campaign with a 6-1, 6-2 win over Colombia's Emiliana Arango on Tuesday as the Pole aims to keep her hot streak on track in New York.
Heading into the final, Gauff had lost the first set in three straight matches and the former U.S. Open champion seemed determined to buck that trend, serving to love in the opening game and breaking early for a 2-0 lead.
Jannik Sinner secured the year-end world number one ranking by beating Czech 30th seed Tomas Machac in the Shanghai Masters semi-finals.