World No.2 Simona Halep and Swiss young gun Belinda Bencic have cemented their Australian Open title credentials with semi-final berths at the Sydney International.

With a glut of women’s heavyweights having pulled the pin in lead-up events due to injury or illness, Halep and Bencic showed it pays to actually be playing less than a week out from the year’s first grand slam.

Halep has been battling an irksome Achilles injury that forced her to withdraw from last week’s Brisbane International.

But the world No.2 has opted to play through the pain and see how far she can push herself, rather than simply preserve her body and hope for the best.

Halep felt it during her three-set defeat of Frenchwoman Caroline Garcia on Tuesday night, and it was there again at Olympic Park on Wednesday when she edged Karolina Pliskova 6-4 7-5, though to a lesser extent.

“I had pain again in second game of second set,” Halep said.

“After that game (it was) gone, so I felt okay today.”

Pliskova, the Czech fifth seed and 2015 Sydney runner-up, didn’t make it easy for Halep, rallying from 5-1 down in the first set and almost taking the tournament’s top seed to a tiebreak in the second.

But Halep is determined to test her Achilles further on Thursday in her semi-final meeting with two-time grand slam champion Svetlana Kuznetsova.

The in-form Russian dismantled Italian Sara Errani on Wednesday, taking control after a hard-fought first set to sweep Errani aside 7-6 (7-1) 6-0.

“I know her pretty well. I’ve played against her,” Halep said of Kuznetsova.

“I know she’s playing a lot of topspin, so it’s a different player tomorrow – different style.

“I like to play against her. I’ve had good matches with her. I expect a tough one.”

Bencic will face Puerto Rican qualifier Monica Puig in the last four after edging Ekaterina Makarova.

The 18-year-old world No.14 looked to have wiped the floor with the Russian after the first set, but was forced to endure a second-set comeback before finally securing victory 6-0 2-6 6-4.

She was visibly frustrated and threw away multiple match points while up 5-4 in the third and serving for the match.

Puig upset Samantha Stosur 6-4 6-4 on Ken Rosewall Arena.