The American-Spanish pair defeated Erin Routliffe of New Zealand and Lloyd Glasspool of Great Britain, 5-3, 4-1.
23-time Grand Slam winner Serena Williams made a comeback to the tennis court earlier this summer. She last played at Flushing Meadows in New York in 2022.
"It's always great to be here. I didn't expect to come back to this court, so it was a 'cool' moment," she says.
Alcaraz made a comeback after a four-month injury layoff.
