.
Kerber couldnt have done anything with her initial shot and she pretty much gave up in set number two, with her minds already being in Melbourne. On the other hand, Petra saved four out of five break points and she was the dominant figure on the court, controlling the rallies with her deep and precise shots that left the better-ranked opponent with no answer.
The battle of the hard-hitting left-handers kicked off with a break for Angelique when Petra sprayed a forehand error in the fifth game, with two more break points up for grabs for the German in game seven that could have pushed her further in front.
Kvitova repelled them with some mighty hitting and she broke back in the following game following a forehand error from Kerber. A forehand winner earned a set point for the Czech in the 10th game and she converted it after a forced error, moving 6-4 up in almost an hour.
Carried by this momentum, Petra rattled off one good service game after another in set number two and she blasted a forehand down the line return winner to secure a break in the fourth game, scoring another one at 4-1 and clinching the win with a service winner in game seven for the place in the semis.
Mertens was the first who threatened on the return, breaking Barty in game three but staying in front only for a couple of minutes before Ashleigh broke back in the next game and again at 3-2 to forge the lead that secured the opening set for her.
The Aussie dominated in the second set as well, stealing the Belgians serve three times in a row and entering the last four with a forehand winner in game nine. .
Kiki lost just eight points on serve and she never faced a break point, keeping the pressure on Putintseva and breaking her four times from five opportunities to cross the finish line in no time at all and march towards the last four.
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