NEW YORK, NEW YORK - AUGUST 30: Stan Wawrinka of Switzerland plays a backhand during a practice session with Carlos Alcaraz of Spain before his first round match at USTA Billie Jean King National Tennis Center on August 30, 2026 in New York City. (Photo by Clive Brunskill/Getty Images)

NEW YORK, NEW YORK - AUGUST 30: Stan Wawrinka of Switzerland plays a backhand during a practice session with Carlos Alcaraz of Spain before his first round match at USTA Billie Jean King National Tennis Center on August 30, 2026 in New York City. (Photo by Clive Brunskill/Getty Images)

NEW YORK, NEW YORK - AUGUST 30: Stan Wawrinka of Switzerland plays a backhand during a practice session with Carlos Alcaraz of Spain before his first round match at USTA Billie Jean King National Tennis Center on August 30, 2026 in New York City. (Photo by Clive Brunskill/Getty Images)

NEW YORK NEW YORK - AUGUST 30: Storm Hunter of Australia looks to return a serve against Marta Kostyuk of Ukraine during their Women's Singles First Round match on Day One of the 2026 US Open at USTA Billie Jean King National Tennis Center on August 30, 2026 in the Flushing neighborhood of the Queens borough of New York City. (Photo by Caleb Bowlin/Getty Images)

NEW YORK NEW YORK - AUGUST 30: Storm Hunter of Australia reacts against Marta Kostyuk of Ukraine during their Women's Singles First Round match on Day One of the 2026 US Open at USTA Billie Jean King National Tennis Center on August 30, 2026 in the Flushing neighborhood of the Queens borough of New York City. (Photo by Caleb Bowlin/Getty Images)

NEW YORK NEW YORK - AUGUST 30: Marta Kostyuk of Ukraine waits for a serve against Storm hunter of Australia during their Women's Singles First Round match on Day One of the 2026 US Open at USTA Billie Jean King National Tennis Center on August 30, 2026 in the Flushing neighborhood of the Queens borough of New York City. (Photo by Caleb Bowlin/Getty Images)

NEW YORK NEW YORK - AUGUST 30: Marta Kostyuk of Ukraine reacts against Storm hunter of Australia during their Women's Singles First Round match on Day One of the 2026 US Open at USTA Billie Jean King National Tennis Center on August 30, 2026 in the Flushing neighborhood of the Queens borough of New York City. (Photo by Caleb Bowlin/Getty Images)

NEW YORK NEW YORK - AUGUST 30: Marta Kostyuk of Ukraine reacts against Storm hunter of Australia during their Women's Singles First Round match on Day One of the 2026 US Open at USTA Billie Jean King National Tennis Center on August 30, 2026 in the Flushing neighborhood of the Queens borough of New York City. (Photo by Caleb Bowlin/Getty Images)