PARIS—When Coco Gauff’s opponent at the French Open on Friday, 30th-seeded Dayana Yastremska, returned to the locker room in Court Philippe Chatrier, she pulled out her phone to study video clips of her 6–2, 6–4 loss to the American.
“I just was really curious what I did wrong,” explained Yastremska, a semifinalist at the Australian Open in January.