Britain's Harriet Dart lost to French Open quarter-finalist Elena Rybakina in the first round at Eastbourne despite a spirited fightback.
Dart, 24, saved a match point in the second set but lost 6-2 6-7 (5-7) 6-4 to the Kazakh world number 21.
Rybakina, 22, who had looked to be struggling with a foot problem, rallied to break Dart twice in the decider.
Meanwhile, defending champion Karolina Pliskova was knocked out of the event where play was washed out on Monday.
The Czech fifth seed started well against Italian qualifier Camila Giorgi but lost 2-6 6-2 6-2, which means the 29-year-old heads into next week's Wimbledon without a win on the grass.
Second seed Elina Svitolina came from behind to beat Spain's Paula Badosa 4-6 6-1 7-6 (7-1).
The 26-year-old Ukrainian has never been past the second round at Eastbourne.
Later on Tuesday, Britain's Heather Watson opens her campaign against Polish world number nine Iga Swiatek.Live scores, results and order of playAlerts: Get tennis news sent to your phone