US Open Day 4: Sabalenka, Alcaraz advance; Townsend-Ostapenko have tense back-and-forth and Raducanu approves of Alcaraz’s buzzcut

Aryna Sabalenka and Carlos Alcaraz advanced at the US Open on Day 4 while Novak Djokovic overcame a slow start to reach the third round. Also on the day in New York, a heated exchange erupted between Taylor Townsend and Jelena Ostapenko. On the sidelines, Daniil Medvedev faced a hefty fine for his on-court outburst.