Maria Sharapova has won her first match at the WTA Championships with a straight-sets victory over Sara Errani.
The Russian dominated the contest from start to finish, dropping just five games all match.
The world number two will next play Agnieszka Radwanska, who won her match against Petra Kvitova.
Sharapova can regain the world number one spot from Victoria Azarenka this week.
