Dubai - Karolina Pliskova, the striking 22-year-old who is part of a new wave on the women's tour, upset the seedings for a second time at the Dubai Open to reach the semi-finals on Thursday.
Pliskova also turned a surprising match dramatically on its head from a set and 1-3 down during a 3-6, 7-6 (7/5), 6-1 win over her 11th seeded compatriot Lucie Safarova.
Last week the six-foot one-inch Czech with one of the steepest and most dangerous first serves in the game reached the Antwerp semis, and last month she became the youngest top 20 player by breaking into the top score for the first time.
However Pliskova had to survive a crisis at 5-5 in the second set when she slipped to 15-40, within one solid blow of probable defeat, before she changed the psychology of the match utterly in an emotion-turning last point of the tie-break.
It happened after Safarova reached the net in a favourable position, only for Pliskova to throw up an adequate lob that enabled her to counter-attack with radar accuracy through a gap in the net-player's coverage.
Her victory followed an even tighter three-set success the previous day against Ana Ivanovic, the fourth-seeded former world number one, and ensured that she maintains one of the eight best win-loss records this year, having hit more than 100 aces.
"I'm really happy that I was able to achieve this," said Pliskova, conscious that Safarova was seeking revenge for defeat in Antwerp and had been buoyed by a straight sets win over titleholder Venus Williams the day before.
"I was able to stay relaxed and that was important," she added, although she acknowledged that she had had an important piece of luck during the climactic moments of the second set tie-break when Safarova was three points from victory.
Embarking on a pair of serves from 4-5 which might have taken her to match point, Safarova was rallying solidly and in a sound position when Pliskova's top spin forehand drive hit the net tape and dropped over, dead and unreturnable.
That gave her two set points and although Safarova saved the first, Pliskova converted the second with the spectacular lob-pass combo which punctured Safarova's morale.
Pliskova broke at once in the final set, broke again for 3-0, and looked a different, more fluent attacker by the end.
Later the tournament gained a breath of fresh air when the first semi-final became a match-up of two players from the new wave, Garbine Muguruza, the 21-year-old from Barcelona, coming through to face Pliskova.
Muguroza achieved this with a 6-7(4-7), 6-3, 6-3 win over her doubles partner Carla Suarez Navarro, the 13th seed who had eliminated former Wimbledon champion Petra Kvitova the night before.
Navarro, with great movement and battling ground strokes, tenaciously saved three set points and snatched the first set.
However, Muguruza, calm and elegantly proficient in all areas of the game, avoided becoming inhibited by score pressure by breaking serve early in the second set.
Thereafter she looked slightly the more likely to win a high-quality encounter full of fluent rallies, although it was not till Navarro delivered a double fault to go 3-5 down in the final set that Muguruza gained her chance to close it out.
"It's not easy to play your doubles partner. We have to play again but on the same side of the net in an hour's time," Muguruza said.
"In the first set I was nervous but I managed to forget that I had lost it - and this was important."
Results in the WTA Dubai Open on Thursday (x denotes seeding):
Karolina Pliskova (CZE x17) bt Lucie Safarova (CZE x11) 3-6, 7-6 (7/5), 6-1
Garbine Muguruza (ESP) bt Carla Suarez Navarro (ESP x13) 6-7(4-7), 6-3, 6-3