Ashleigh Barty beat Karolina Pliskova 2-6 6-1 7-5 to progress to the semi-final stage of WTA Stuttgart.
Barty, competing at her first red clay-court tournament since winning Roland Garros in 2019, fought back from a set down to force a decider. However, the world number one found herself on the cusp of defeat at 5-3 in the final set.
The 24-year-old rallied to win the next four games on the bounce to seal a spot in the semi-final.
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"In a sense it was probably a match of two sets," said Barty.
In the first set I wasn't able to build any pressure. Kaja was getting in and out of her serving games too quickly, and in turn was then having freedom on my service games.
“But being able to flip that switch right from the first game of the second set was important. To then make it more of a physical match was what we were after, and over time we were able to get the match back on my terms as much as we expected."
Awaiting Barty in the last four will be Elina Svitolina after the world number five saved two match points to beat defending champion Petra Kvitova 6-7 7-5 6-2.
"A big battle is always very satisfying, and you know that the hard work pays off," Svitolina said.
It’s always an unbelievable feeling to go through this kind of match.
Elsewhere, second seed Simona Halep beat Ekaterina Alexandrova 6-1 6-4. The two-time Grand Slam winner, who lost her previous two encounters against the Russian, is yet to drop a set in Stuttgart this week.
"I knew she would play fast and flat, so I had to make her run more - I learnt my lesson," Halep said after the match.
The Romanian world number three will play either Aryna Sabalenka or Anett Kontaveit in the semi-final.
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