Ash Barty has produced another extraordinary comeback to beat former World No.1 Karolina Pliskova in Stuttgart.
The Aussie star had to fight back from a set down to reach the semi-finals of the clay-court event on Friday, prevailing 2-6, 6-1, 7-5.
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The World No.1 showed incredible resilience after a dream first set in the quarter-final by Pliskova, who broke Barty twice.
But Barty broke the Czech to start the second set, which set the stage for her comeback.
Pliskova, the 2018 Stuttgart champion, served for the match at 5-4 in the decider but couldn't close it out as Barty converted her fifth break point in a marathon game.
Barty then held to love and secured victory in the following game on her second match point.
"It was an incredible match, with two very different opening sets, and the third was extraordinary," said Barty after her 18th win this year.
"I felt like I created a lot of opportunities and Karolina was able to come up with some quality stuff on some massive points.
"It was a really good battle."
Barty to face Svitolina in Stuttgart semi-final
With victory over the World No.9, Barty is now 8-0 in her last eight matches against top-10 opponents.
Barty will face fourth seed Elina Svitolina in Saturday's semi-final after the Ukrainian staged a remarkable comeback in her 6-7 (4/7), 7-5, 6-2 win over Petra Kvitova.
"I missed some returns, but Karolina is a fierce competitor who has been at the top of her game for a long time," said Barty, the 2019 French Open winner.
"I knew I'd have to do something special to claw my way back and get back on my terms."
Asked on court in the crowd-free arena whether it had been the sort of game that made her love tennis, Barty said: "Absolutely. When it's so close like that, I felt like I brought out some of my better tennis when I had to.
"And that's what I love about this sport.
"It's a funny scoring system, you're never out of it and you just have to keep trying every time you step up to the line to serve or return."
It was another compelling demonstration of Barty's ability and spirit because even though she initially struggled with her movement on the unusual clay-over-boards surface, she still adapted ably enough to largely dictate over the last two sets.
Svitolina produces epic comeback of her own
Meanwhile, Svitolina was 5-2 down in the second set but saved two match points as she reeled off five games on the bounce against 2019 champion Kvitova.
She broke the two-time Wimbledon winner twice in the third set to complete an improbable quarter-final turnaround.
"It was a really tough battle, I was expecting a big match but I didn't think it would be that hard," admitted Svitolina.
The World No.5 has lost her last two matches against Barty, most recently in the semi-finals of this year's Miami tournament.
"We played each other in Miami a few weeks ago, we know each other's game very well, so I am looking forward to it," said Svitolina.
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