Wimbledon 2015: Serena Williams sets up Maria Sharapova semi-final with a hard-fought win over Victoria Azarenka

The American remains on course for her calender grand slam bid

Serena celebrates during her victory over Victoria Azarenka (GETTY IMAGES)

Serena Williams out-slugged Victoria Azarenka to set a frosty Wimbledon semi-final with Maria Sharapova and keep her calendar grand slam bid firmly on track.

The reigning Australian and French Open champion is now the overwhelming favourite to complete the third leg of that calendar slam, with no other true big-hitters left in the Wimbledon draw.

Only former world number one Azarenka had the power to match Williams, and even she could not cope, the 20-time major champion triumphing 3-6 6-2 6-3

PA