Hingis was far from impressive in her victory over Mirza

Hingis won 6-3 7-5 against an opponent who also failed to find any consistency in front of a rowdy sell-out crowd.

The Swiss player took the first set on her fourth set point after fighting off a break point at 5-3.

In the second set, she broke three times but allowed Mirza to level on each occasion before securing the win.

"I felt I had the game under control and whenever I needed it I was able to step it up," said Hingis.

Russian fifth seed Nadia Petrova fell 6-4 6-1 to compatriot Maria Kirilenko, but there were wins for seventh seed Francesca Schiavone of Italy and Russia Svetlana Kuznetsova.