British number one Johanna Konta beat Ukrainian Lesia Tsurenko to reach the second round of the Aegon Classic in Birmingham.
Fourth seed Konta battled to a 6-3 7-6 (8-6) win against the world number 34.
Tsurenko had the chance to serve for the second set at 5-3 but Konta broke back and went on to win the tie-break by converting her third match point.
The world number seven will face either Christina McHale or fellow American Coco Vandeweghe in the next round.
Konta, 26, is pursuing a first WTA title on grass having lost to Croatia’s Donna Vekic in the final of the Aegon Open in Nottingham last week.
She appeared to be unwell midway through the second set and needed a medical timeout, but after the match said: “Yes, I am fine. I’m good.”
The Australian-born right-hander added: “I am very happy to come through it in two, she was playing well and I had to keep fighting and not get too far ahead or too far behind.”
Two-time Wimbledon champion Petra Kvitova overcame fellow Czech Tereza Smitkova 6-2 6-3 to set up a second-round match against British number two Naomi Broady.
Kvitova, the world number 16, was competing in only her third match since suffering a hand injury in a knife attack at her home in December, having gone out in the second round of the French Open last month.
Slovakian world number six Dominika Cibulkova went out to Czech Lucie Safarova 7-5 6-7 (7-9), while 2015 Wimbledon finalist Garbine Muguruza of Spain won 6-3 3-6 6-4 against Russia’s Elizaveta Kulichkova.