Caroline Wozniacki fought back from a set down to defeat Sara Errani and reach the last eight of the Istanbul Cup on Thursday.

At her first clay-court tournament of the season, top seed and 2014 winner Wozniacki encountered few problems in seeing off Ekaterina Alexandrova 6-2 6-2 in the opening round two days previously.

But she was forced to do it the hard way against Errani before eventually progressing 5-7 6-3 6-3 to set up a quarter-final meeting with Pauline Parmentier.

Wozniacki, the Australian Open champion, fought back from 5-2 down in the first set to level at 5-5 but was promptly broken again before Errani held to edge ahead.

That was as good as it got for the Italian, however, as Wozniacki romped into a 4-0 lead en route to levelling the match, before storming 4-1 ahead in the decider and closing out victory against the serve as Errani dumped a forehand into the tramlines.

Danka Kovinic, runner-up at this WTA International event two years ago, was beaten 2-6 6-2 6-0 by Arantxa Rus, who will now face Maria Sakkari - a 6-3 6-1 victor over Aleksandra Krunic.

Meanwhile, Polona Hercog was leading 6-2 1-1 when Kateryna Bondarenko retired and Donna Vekic made light work of Ajla Tomljanovic, prevailing 6-1 6-2.