Two-time champion Kvitova was the pre-tournament favourite, but her hopes of adding another title were soon over as she went down to Aliaksandra Sasnovich in three sets.

World number one Halep and defending champion Muguruza had no such problems, as the majority of the other seeds progressed.

Caroline Garcia and Sharapova were not among them, however, the world number six losing to Belinda Bencic in straight sets as the 2004 champion threw away a one-set lead to qualifier Vitalia Diatchenko.

Defeat at the hands of the world number 132 represents the first time that Sharapova has lost in the first round at the All England Club.