Kvitova battles through to semis

Petra Kvitova overcame a mid-match slump to overcome Sara Errani and progress to the Australian Open semi-finals.

The Wimbledon champion dictated early on but, having won the first set, lost her way before hitting back to win 6-4 6-4.

With her big-hitting game, the match was always going to be played on Kvitova's terms against the smaller Italian.

So it proved as the rallies were won or lost by the Czech with Errani simply trying to make it as difficult as possible for her opponent. And for the most part she did a good job.

With service holds at a premium, the opening set came down to Kvitova's consistency and she held it together long enough to claim it in 53 minutes.

She looked on her way to a routine win when she also claimed the Errani serve at the start of the second. But the world number 48, appearing in her maiden grand slam quarter-final, had other ideas as Kvitova's game started to disintegrate.

But Kvitova, sensing the match was getting away from her, refocused and having held for 2-4, reeled off another four games in a row, reasserting her authority from the baseline. "I expected it to be tough," said Kvitova. "She played very well today and also over the past few days. I didn't expect it to be easy."

Meanwhile, Maria Sharapova got the better of Russian compatriot Ekaterina Makarova to advance to a semi-final meeting with Kvitova.

In a match of hard-hitting baseline rallies, fourth seed Sharapova possessed the greater accuracy, particularly at the key moments, to move through 6-2 6-3.

Makarova, the world number 56 and appearing in her first grand slam quarter-final, acquitted herself well but was not able to make enough headway on the Sharapova serve.