Second seed Simona Halep has crashed out in the first round of the Australian Open by going down in straight sets to Chinese qualifier Zhang Shuai.

Halep, who has reached the quarter-finals the last two years in Melbourne, was on the back foot from the word go as Zhang raced out to a 4-0 lead with two breaks of serve.

The world number 133 was then pegged back as Romanian Halep won four of the next five games to get back on serve, but she could not level the set as Zhang broke once more in the 10th game to snatch the opener 6-4.

Halep came out fighting at the start of the second and moved into a 3-1 lead before Zhang reeled off five games in a row to clinch victory in an hour and 19 minutes.

Zhang, who reaches the second round of a Grand Slam for the first time in 15 attempts, will next face world number 33 Alize Cornet in Melbourne.