Heartbreak for Alex de Minaur in sad twist around girlfriend Katie Boulter at Aus Open

Not only is Alex de Minaur the only Aussie left in action at the Australian Open, he's also the only half of his relationship with Katie Boulter still playing. Boulter suffered double heartbreak on Thursday at Melbourne Park, losing to Zheng Qinwen in the singles before also crashing out of the doubles.

Boulter was no match for 12th seed Zheng, going down in straight sets 6-3 6-3. She was then dumped out of the doubles competition, with the British player and Petra Martic losing to fifth seeds Laura Siegmund and Barbora Krejcikova 6-2 6-1.

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Boulter, who has been dating Aussie star de Minaur for the last few years, was up 3-2 with a break in the second set against Zheng. But she didn't win another game, as the Chinese player rattled off four-straight to prevail.

The British player would have been hoping to make a deep run at Melbourne Park to match or better the feats of her boyfriend. De Minaur is the only Australian man left in the singles draw, and entered Friday's play as one of just two local players left in action along with Storm Hunter.

Boulter will now pin her hopes on de Minaur, who beat Flavio Cobolli 6-3 6-3 6-1 on Friday night to book his place in the fourth round. Hunter lost to Krejcikova in three sets later on Rod Laver Arena.

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The Aussie contingent was decimated on Thursday as Ajla Tomljanovic, Thanasi Kokkinakis and Max Purcell all bowed out. Tomlajnovic lost 6-0 3-6 6-4 to Jelena Ostapenko, Kokkinakis went down 6-3 6-2 4-6 6-4 to Grigor Dimotrov, while Purcell pushed 11th seed Casper Ruud before succumbing 6-3 6-7 (5-7) 6-3 3-6 7-6 (10-7).

But de Minaur showed why he entered as red-hot favourite against World No.100 Cobolli, with previous wins over an injured Milos Raonic and Italian Matteo Arnaldi leaving him with plenty in the tank. Raonic retired hurt early in the third set, before de Minaur dispatched Arnaldi whil conceding just six games.

"Over the years I've come to learn how important it is to, if possible, conserve the energy because it is a long two weeks if you want to get to the end of the tournament, and that's ultimately the goal," de Minaur said. "The first week is all about finding ways to get through - it might not be your best tennis, but if you get through the first week, you give yourself a chance in the second week to show what you're made of."

Ajla Tomljanovic backs Storm Hunter to shine in singles

Hunter - the World No.1 doubles player - was a huge underdog against Krejcikova, but Tomljanovic showed plenty of belief in her compatriot. "I have been telling Storm for a while now she needs to start playing singles only," Tomljanovic said after her loss on Thursday night. "She already proved she's the best in doubles - so she hasn't listened to me yet. I think she can do amazing things in singles.

"She's been amazing in Billie Jean King Cup over the last couple of years - and she's clutch. Seeing her have success here at home is really awesome because she can play at that level, but I do think it's hard to do that when you are playing such a high level of doubles and your ranking is not quite there with your singles. In my opinion, she's going to have to make a decision at some point. I feel like she proved here that she really does belong at the higher level in the singles game."

with AAP

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