Alison Riske became the first player to reach the second round at Wimbledon.
The 28th-seeded American beat Ylena In-Albon of Switzerland 6-2, 6-4 on Court 10.
Third-seeded Ons Jabeur advanced a short time later, completing her 6-1, 6-3 victory over Swedish qualifier Mirjam Bjorklund.
Jabeur reached the quarterfinals at the All England Club last year and won a grass-court title in Berlin heading into this year’s tournament.
