Garbine Muguruza has withdrawn from the Sydney International due to injury less than a week before the Australian Open gets under way.

Cramps forced the Wimbledon champion to pull out of the Brisbane International last week and the 24-year-old retired in Sydney due to an issue with her right thigh.

Wildcard entry Muguruza beat Kiki Bertens 6-3 7-6 (8-6) on Wednesday, but it was later announced that she will not play in the quarter-finals.

Muguruza took a medical timeout after the third game against Bertens, but was able to continue and seal her first win of the season.

The Spaniard's latest setback comes just five days before the opening grand slam of the year starts in Melbourne.