U.S. Open champion Naomi Osaka said her breakthrough victory in New York last month still felt "bittersweet" and is hoping that a strong end to the season could help her to feel better.
Osaka's triumph in the U.S. Open final was overshadowed by a row between her opponent Serena Williams and chair umpire Carlos Ramos, which resulted in the 23-time Grand Slam champion being docked a game and fined $17,000.
The 20-year-old Osaka was reduced to tears as she waited to be handed her maiden major trophy and an angry crowd at Flushing Meadows took out their frustration on Ramos.