Ash Barty opponent's 'horrendous' act stuns fans at Australian Open

Amanda Anisimova had the game on her racquet.

The young American was taking it to Ash Barty and threatening to cause a major boilover in their fourth round clash at the Australian Open on Sunday night.

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Even after dropping the opening set, the big-hitting 20-year-old continued to take the fight to the title favourite.

She broke the top seed in the second game of the second set, snapping Barty's incredible streak of 63 consecutive service games held, to briefly silence the Rod Laver Arena crowd.

But one unfathomable error came back to haunt her and effectively ended her campaign at Melbourne Park. (Watch the incident in the video below).

With Anisimova serving at 3-3, 40-15 in the second set, the 20-year-old had an easy putaway smash to seal the game and take a 4-3 lead.

However Anisimova shanked the overhead volley terribly, sending it long and keeping Barty in the game.

And the Australian World No.1 didn't miss her chance, storming back to break Anisimova's serve and take the decisive lead in the second set.

Barty went on to win 6-3 6-4 to punch her ticket to the quarter-finals and leave Anisimova ruing her costly error.

Renowned tennis administrator Craig Gabriel tweeted: "Ash Barty breaks in the second set to lead 4-3.

"Amanda Anisimova had 40-15 on serve and played a horrendous smash and Ash struck."

Ash Barty marches on in Australian Open quest

Barty passed her sternest test yet on Sunday night to move safely into the Australian Open quarter-finals in Melbourne.

The World No.1 dropped serve for the first time all tournament before seeing off US prodigy Anisimova in one hour and 14 minutes.

The 25-year-old Wimbledon champion is the first home hope to reach at least the last eight of the Open for four consecutive years since Wendy Turnbull in 1984.

But having come this far before - and beyond - and failed to walk away with the trophy she most covets, Barty modestly played down Rod Laver's gushing praise for his in-form compatriot.

Enjoying a front-row view of Barty in the arena named in his honour, Laver declared the top seed "unbeatable" while playing as imperiously as she has this summer.

"He was unbeatable. I'm certainly not," Barty said.

"I'm just out here doing what I can, enjoying it.Try and make my opponent's life as uncomfortable as possible. That's my job, ultimately.

"Obviously (Laver) is an exceptional human being. He's an amazing champion of our sport. He's iconic. It's just amazing to be in his presence."

Hoping to break the host country's 44-year Open singles title drought, Barty will play another American, 21st seed Jessica Pegula, on Tuesday for a place in the last four.

"It was nice to be able to hold firm tonight and bring the points back into my patterns more regularly and the big ones when it mattered most," Barty said.

"Amanda's an incredible athlete. She's an incredible competitor. One of the best attributes is that she's able to turn up point after point after point.

"I enjoyed testing myself against her. She's got an exceptional game that puts you under the pump right from the get go.

"It's just nice to see her back playing her best tennis. She's a champion. She's going to be in deep stages of a lot of majors in her future, that's for sure."

with AAP

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