NEW YORK, NEW YORK - SEPTEMBER 07: Karen Khachanov returns a shot against Learner Tien of the United States during their Men's Singles Fourth Round match on Day Nine of the 2026 US Open at USTA Billie Jean King National Tennis Center on September 07, 2026 in the Flushing neighborhood of the Queens borough of New York City. (Photo by Patrick Smith/Getty Images)

NEW YORK, NEW YORK - SEPTEMBER 07: Learner Tien of the United States returns a shot against Karen Khachanov during their Men's Singles Fourth Round match on Day Nine of the 2026 US Open at USTA Billie Jean King National Tennis Center on September 07, 2026 in the Flushing neighborhood of the Queens borough of New York City. (Photo by Patrick Smith/Getty Images)

France's Arthur Gea pumps his fist as he plays Netherlands' Botic van de Zandschulp in their men's singles round of 16 tennis match on day nine of the US Open tennis tournament at the USTA Billie Jean King National Tennis Center in New York on September 7, 2026. (Photo by Leonardo MUNOZ / AFP via Getty Images)

France's Arthur Gea pumps his fist as he plays Netherlands' Botic van de Zandschulp in their men's singles round of 16 tennis match on day nine of the US Open tennis tournament at the USTA Billie Jean King National Tennis Center in New York on September 7, 2026. (Photo by Leonardo MUNOZ / AFP via Getty Images)

Belgium's Alexander Blockx celebrates defeating Argentina's Francisco Cerundolo in their men's singles round of 16 tennis match on day nine of the US Open tennis tournament at the USTA Billie Jean King National Tennis Center in New York on September 7, 2026. (Photo by KENA BETANCUR / AFP via Getty Images)

Belgium's Alexander Blockx celebrates with his team after defeating Argentina's Francisco Cerundolo in their men's singles round of 16 tennis match on day nine of the US Open tennis tournament at the USTA Billie Jean King National Tennis Center in New York on September 7, 2026. (Photo by KENA BETANCUR / AFP via Getty Images)

Iga Swiatek, of Poland, receives a massage during a medical timeout durnig a match against Qinwen Zheng, of China, during the fourth round of the U.S. Open tennis championships, Monday, Sept. 7, 2026, in New York. (AP Photo/Seth Wenig)

Iga Swiatek, of Poland, returns the ball to Qinwen Zheng, of China, during the fourth round of the U.S. Open tennis championships, Monday, Sept. 7, 2026, in New York. (AP Photo/Seth Wenig)