Reigning Wimbledon champion Petra Kvitova overcame tenacious Italian Sara Errani in straight sets to reach the semi-finals of the Australian Open on Wednesday.
The world number two from the Czech Republic was troubled by the clever Errani before winning 6-4, 6-4 to move into a semi-final against either Maria Sharapova or Ekaterina Makarova.
Kvitova is the first Czech woman to reach the semi-finals of the Australian Open since Jana Novotna in 1991, but she had to use all her resources to get to the final four.
The 21-year-old was always favoured to win against Errani, but the gritty Italian fought all the way in the first set, using a variety of shots to upset the world number two.
Kvitova broke Errani three times in the first set but lost her serve twice herself as the Italian made up for a lack of power with superb court coverage and clever shot-making.
The Czech won a tight first set in 53 minutes, but after breaking Errani to start the second she dropped her own serve twice to allow Errani to skip away to a 4-1 lead.
Kvitova was becoming increasingly frustrated with Errani's tactics and several times looked towards her coach in despair after missing easy shots.
But she dug deep to hold serve, and then broke Errani after a long struggle to get the set back on track. Kvitova then stepped up and found her range, winning the next three games to go through.
"I always expected it to be tough, she played well today and in the days before," Kvitova said.
"Her forehand, I didn't know where it was going to go so it was hard to concentrate on every point and think about tactics."