Defending champion Carlos Alcaraz returned to singles action with a victory after a 139-day absence, while Aryna Sabalenka began her bid for a third consecutive U.S. Open title with a winning start Monday, providing plenty of star power on the second day of the year's final Grand Slam.
Former champion Iga Swiatek and last year's runner-up Amanda Anisimova also advanced with convincing victories, while Stefanos Tsitsipas delivered one of the day's biggest upsets by knocking out No. 10 seed Arthur Fils on a sunny afternoon in New York.
Alcaraz entered the tournament with questions surrounding his fitness after spending nearly four and a half months sidelined by a wrist injury. But the Spaniard quickly eased those concerns, cruising past Russia's Roman Safiullin 6-4, 6-4, 6-4 in his first competitive singles match since his injury.
"You don't know what's going to happen in the match after 4 1/2 months almost," Alcaraz told reporters. "You don't know what's going to happen in your body, in your mind, everything. It's totally different.
"But I just tried to play one game at a time and tried to feel good, to enjoy playing points, feeling the love from the people. Hopefully they enjoyed it."
