World No.1 Ash Barty suffered a meltdown on the brink of victory but regathered herself to fend off compatriot Daria Gavrilova 6-1 7-6(7) and reach the third round of the Australian Open on Thursday.
Barty, who came onto centre court with her left thigh heavily strapped, served for the match at 5-2 but was broken twice in a hail of unforced errors, allowing wildcard Gavrilova to drag the contest deep into a tiebreak.
Fortunately for Barty, Gavrilova reprieved her twice with unforced errors on set point and then coughed up another on match point to surrender on a steamy day at Rod Laver Arena.
Barty will meet the winner of Ekaterina Alexandrova and Barbora Krejcikova for a place in the fourth round.
Defending champ crashes out
Reigning champion Sofia Kenin crashed out of the Australian Open in the second round on, slumping to a 6-3 6-2 defeat at the hands of world No.65 Kaia Kanepi on Margaret Court Arena.
Kenin, who followed her Grand Slam breakthrough at Melbourne Park last year with a run to the final at the French Open, sprayed 22 unforced errors in the 64-minute contest against the experienced Estonian.
Other second round women's results on Thursday
Ukraine's fifth seed Elina Svitolina produced a clinical display to beat American teenager Coco Gauff 6-4 6-3.
Estonian 21st seed Anett Kontaveit recovered from a shaky start to beat Britain's Heather Watson 6-7(5) 6-4 6-2 and set up a third-round meeting with American Shelby Rogers.
Switzerland's 11th seed Belinda Bencic needed five match points to put away two-time Grand Slam champion Svetlana Kuznetsova 7-5 2-6 6-4.
Sixth seed Karolina Pliskova, who reached the semi-finals at Melbourne Park two years ago, booked a place in the third round with a 7-5 6-2 victory over American Danielle Collins.