Twice former champion Petra Kvitova overcame a second-set wobble to reach the Wimbledon third round with a 6-1 7-6(5) defeat of Romanian Ana Bogdan on Thursday.
The big-hitting Czech, seeded 25th, was cruising at 6-1 5-1, but Bogdan staged a remarkable comeback.
Kvitova had a match point when serving at 5-4 but was broken for the second time in a row as Bogdan levelled.
Bogdan then had two set points as Kvitova served at 5-6, one saved with an ace, the other with a forehand winner.
A relieved Kvitova finally got the job done in the tiebreak when Bogdan's backhand found the net under pressure.
Kvitova, champion at Wimbledon in 2011 and 2014, will now play Spain's fourth seed Paula Badosa who enjoyed a comfortable 6-3 6-2 win over Irina Bara, also of Romania.
Since winning her second title, Kvitova has only managed to reach the Wimbledon fourth round on one occasion but is in good form after winning the Eastbourne grasscourt title last week.