Petra Kvitova ended hopes of a home singles champion at the Australian Open with a crushing victory over Ashleigh Barty in the quarter-finals.

Barty was the first Australian woman to reach the last eight for 10 years and there was optimism she could become the first home winner since Chris O'Neil in 1978, but Kvitova was in devastating form in a 6-1 6-4 victory.

The Czech has not lost more than five games in any of her matches so far and is through to the last four at a slam for the first time since winning her second Wimbledon title in 2014 and a little over two years after fearing she might never play again when she was stabbed in the hand by an intruder at her home.

Kvitova's victory, meanwhile, ensures Simona Halep will be replaced as world number one, although Naomi Osaka, Karolina Pliskova and Elina Svitolina are also in the frame.

Kvitova began her on-court interview by apologising to the deflated crowd, saying: "I'm sorry guys. She's such a nice person and you should be very proud of her.

"It was a great match definitely. She came back well, she didn't give me anything for free and I really had to fight until the end."

The 28-year-old became emotional when asked about the struggles she has been through, choking back tears as she said: "I didn't really imagine to be back in this great stadium, it's great."

Kvitova's comeback has been one of the sport's more remarkable stories but her failure to back up impressive form on the WTA Tour at the grand slams last year meant she arrived in Melbourne with little fanfare despite winning the warm-up tournament in Sydney.

In the final a little over a week ago she defeated Barty in a tight tussle decided by a third-set tie-break after the Australian had won the opening set for the loss of only one game.

Here it was Kvitova who raced through the opener, her clean power-hitting too much for Barty, who looked to be feeling the weight of expectation upon her shoulders.

The 22-year-old dug in at the start of the second set and began to disrupt Kvitova's rhythm but chances to break came and went in the opening two games and, when the Czech seized her opportunity at 5-4, the end swiftly followed.