Australian Open 2012: Caroline Wozniacki wrist injury

Wozniacki hopes wrist injury will not wreck her Australian Open bid

Caroline Wozniacki suffered a wrist injury just five days before the start of the Australian Open as she lost to Agnieszka Radwanska in the quarter-finals of the Sydney International on Wednesday.

The top seed had her left wrist strapped during the final set of her 3-6 7-5 6-2 defeat and could now lose her number one ranking to Czech player Petra Kvitova before the first Grand Slam of the year gets under way.

The Dane is hoping to end her wait for a first Grand Slam trophy of her career in Melbourne and believes she will be fit for the start of the tournament.

Hopeful: Caroline Wozniacki hopes the injury is not serious

Hopeful: Caroline Wozniacki hopes the injury is not serious

Progress: Agnieszka Radwanska is in the next round

Progress: Agnieszka Radwanska is in the next round

'I hope it's not serious,' she told www.eurosport.com.

'I could feel it today, especially in the third set. I'm going to go get it checked out tomorrow and hopefully it's okay. Let's just hope for the best.

'I should be completely fine for Australian Open. I started feeling it more and more during the match.'

The injury seemed to affect Wozniacki's serving as she was broken eight times, winning fewer than 50% of points on both her first and second serves as she lost in two hours 38 minutes.

Poland's Radwanska will next face third seed Victoria Azarenka, who was pushed hard by Marion Bartoli before claiming a 7-5 6-4 win.

It was a real slog for the Belarusian, who needed four breaks in the first set and three in the second to get the job done in nearly two and a half hours.

The other semi-final will be between second seed Kvitova and fourth seed Li Na.

Kvitova was in irresistible form as she breezed past Daniela Hantuchova 6-0 6-4 in a little over an hour, while Li beat Lucie Safarova 6-2 7-6 (7/3).

Kvitova will take the number one ranking if she wins the tournament.

Hunt: Wozniacki is looking for her first Grand Slam trophy

Hunt: Wozniacki is looking for her first Grand Slam trophy

Second seed John Isner was the big casualty in the men's draw, beaten in three sets by fellow American Bobby Reynolds in their last-16 match.

Isner seemed to be on course for a simple victory against his 126th-ranked opponent when he took the first set, but took his foot off the gas to slip to a 3-6 6-4 6-3 defeat.

First and third seeds Juan Martin Del Potro and Richard Gasquet were straight-sets winners over Lukasz Kubot and Fabio Fognini respectively, but the fourth, fifth and eighth seeds all slipped up.

KO: John Isner was knocked out by fellow American Bobby Reynolds

KO: John Isner was knocked out by fellow American Bobby Reynolds

Feliciano Lopez lost 6-3 6-4 to Julien Benneteau, Viktor Troicki was beaten 7-6 (7/5) 6-4 by Alex Bogomolov Jr and Radek Stepanek came up short in a three-setter against Jarkko Nieminen, 7-6 (7/5) 5-7 6-1.

Also advancing to the quarter-finals were Denis Istomin and Marcos Baghdatis.