Maria surprised by impressive form

Maria Sharapova is used to having to rebuild from scratch after suffering a string of debilitating injuries throughout her career, but the Russian is still surprised at how well she is playing in her latest comeback at the WTA Finals.

Sharapova arrived in Southeast Asia having failed to complete a match since July because of leg and arm injuries, but the five-time major winner has looked in ominous form since setting foot on the Singapore Indoor Stadium court on Sunday.

Round-robin wins over Agnieszka Radwanska and Simona Halep were followed by a classy 7-5, 6-1 victory over US Open champion Flavia Pennetta on Thursday as the 28-year-old advanced to the semifinals, top of the Red Group with a perfect record.