Magdalena Rybarikova became the first seed of Wimbledon 2018 to lose as she was beaten by Sorana Cirstea.
The 19th seed, who reached the last four in Birmingham a fortnight ago, was downed 7-5 6-3 by the Romanian.
Yanina Wickmayer was the first winner of this year's tournament as she beat Mona Barthel.
The unseeded Belgian defeated Barthel 7-5 6-4 on Court 18 to become the first woman through to the second round.
