Muguruza withdraws from Sydney

Australian Dasha Gavrilova defeated compatriot Samantha Stosur in the second round of the Sydney International and made the final eight.

This delivered her a challenging quarter final against top seed Garbine Muguruza.

However, the world number three, who had withdrawn from the Brisbane International with cramps before finishing her first match, suffered a thigh injury early in her second round battle with Kiki Bertens (again her first match of the tournament).

Despite defeating Bertens in straight sets, Garbine withdrew from her quarter final, handing Gavrilova a free pass to the semis.

Muguruza’s two successive withdrawals and injury woes are a major concern with the Australian Open only days away.

And organisers certainly don’t want another top player dropping out, adding to Serena Williams, Andy Murray and Vika Azarenka.

The three quarter finals that will actually hit the tennis court are:

Barbora Strycova v Ash Barty in a high quality unseeded clash

Strycova had already booked her spot by dumping Makarova and Barty shifted fellow Australian Ellen Perez out of her path to glory.

Camila Giorgi v Aga Radwanska in another unseeded match

Giorgi has deleted two Grand Slam champions en route to the final 8 - Sloane Stephens and Petra Kvitova.- and hasn’t dropped a set.

Kvitova took Giorgi to a first set tiebreaker but lost it 9-7.

Giorgi must have been relieved, having wasted seven break points prior to winning the tie break.

Set two was a breeze in comparison, the Italian out serving the dual Wimbledon title holder and proceeding to take the match 7-6(7) 6-2.

Dominika Cibulkova v Angie Kerber - yes a third unseeded quarter final

Angie has won an Australian Open and Domi has been a finalist - here they have eliminated seeds - Cibulkova knocked out Sevsstova (8) in round one with a huge punch and Kerber finally had the better of Venus Williams (2) after donating the opening set to the American.

So the winner of the Sydney International will be unseeded - not such a huge surprise considering the considerable quality and depth of the field assembled for the event this year.

21 of the top 33 ranked women were in the draw at the start.

Quarter finals in Auckland:

Peter Gojowczyk v Robin Haase - Gojowczyk defeated top seed Jack Sock in the second round

Jiri Vesely v Roberto Bautista Agut (5) - Vesely defeated Sam Querrey (3) in the second round

David Ferrer (7) v Hyeon Chung - Chung eliminated John Isner (4) in the second round

Karen Khachanov v Juan Martin del Potro (2) - Khachanov defeated Pablo Cuevas (6) in the second round

Quarter finals in Hobart:

Aryna Sabalenka v Lesia Tsurenko (5) - Sabalenka defeated top seed Shuai Zhang in round two 

Mihaela Buzarnescu v Alison Riske - Buzarnescu defeated Alize Cornet (4) in round one and Alison Riske eliminated Katerina Siniakova (8) also in round one 

Donna Vekic v qualifier Heather Watson - Vekic defeated Tatjana Maria (7) and Watson defeated Sorana Cirstea (3), both in the first round

Qualifier Monica Niculescu v Elise Mertens (2) - Niculescu eliminated Irina-Camelia Begu (6) in the opening round