MELBOURNE, Australia – Martina Hingis and Sania Mirza were held up for longer than usual en route to the last four of the Australian Open, eventually seeing off the stubborn resistance of Anna-Lena Groenefeld and CoCo Vandeweghe on Tuesday afternoon.

Having romped through their opening three assignments at Melbourne Park, Hingis and Mirza made the perfect start against No.12 seeds Groenefeld and Vandeweghe, pocketing the opening set in a brisk 23 minutes.

Thoughts of another routine victory were soon parked as their opponents capitalized on some uncharacteristically sloppy mistakes to level to contest. There, though, the surprises ended as the top seeds steadied the ship, breaking twice to close out a 6-2, 4-6, 6-1 victory.

The result extends Hingis and Mirza’s remarkable winning streak to 34 matches – a run stretching back to the end of last summer and bringing seven titles.

And their path to number eight was made a little simpler with the exit earlier in the day of No.2 seeds Chan Yung-Jan and Chan Hao-Ching.

The sisters were the last team to get the better of Hingis and Mirza, coming out on top in the Cincinnati semifinals, but their hopes of reaching a maiden major final together were dashed by Andrea Hlavackova and Lucie Hradecka, 2-6, 7-5, 6-3.

No stranger to the business end of a Grand Slam – they lifted the French and US Open crowns in their first stint together – Hlavackova and Hradecka will now meet Xu Yi-Fan and Zheng Saisai, 6-2, 5-7, 6-4 winners over home hopes Anastasia and Arina Rodionova in the evening session.