Cirstea stuns Stosur at Australian Open

US Open champion Samantha Stosur was stunned in the Australian Open's first round on Tuesday as she crashed out in straight sets to Romania's Sorana Cirstea in front of her home crowd.

Cirstea took advantage of a host of unforced errors from the Australian sixth seed to win 7-6 (7/2), 6-3 on her fourth match point and continue Stosur's miserable run in Melbourne.

Stosur becomes the biggest casualty so far at this year's Open as she failed to follow a series of easy wins by many of the other women's favourites.

The 27-year-old has admitted she struggles with the expectations of local fans after losing in the second round in Brisbane and in the first round in Sydney this month.

On the Australian Open's central court, Stosur made far too many unforced errors against Cirstea, most of them coming off her usually favoured forehand side.

Cirstea, the world number 59, was content to keep the ball deep in the court and wait for mistakes from the Australian's racquet.

She won the first set tiebreak easily and after early trades of service breaks in the second set, Cirstea secured a vital break in the fifth game, then held her nerve to move to a 5-3 lead.

Stosur's normally reliable serve cracked as Cirstea brought up her first two match points at 15-40.

The Australian saved both but couldn't close out the game, and Cirstea eventually clinched victory when a Stosur forehand sailed long -- her 33rd unforced error of the match.

"Probably the whole of Australia hates me right now," Cirstea said. "I think everyone was talking about her (in the lead-up) and they were forgetting about me."