Samantha Stosur of Australia hits a return against Carla Suarez Navarro of Spain in their women's singles match on the third day at the Brisbane International tennis tournament on January 5, 2016. AFP PHOTO / Saeed KHAN -- IMAGE RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE / AFP / SAEED KHAN (Photo credit should read SAEED KHAN/AFP/Getty Images)

Sam Stosur has suffered a shock first round exit from the Australian Open at the hands of Czech qualifier Karolina Pliskova.

Pliskova defeated Stosur 6-4, 7-6 to advance to the second round.

The 31-year-old Australian failed to capitalise on an underdone Pliskova, who twice called for the trainer during the match.

Once again it was unforced errors that cost Stosur, hitting 33 unforced errors in two sets, compared to just 23 winners.

Stosur's biggest weapon, her serve, also let her down at pivotal moments, with a first serve percentage of just 54 per cent.

Pliskova will face Monica Puig in the second round.