Maria Sharapova of Russia hits a return to Agnieszka Radwanska of Poland during their WTA Finals singles tennis match at the Singapore Indoor Stadium October 24, 2014. [Photo/Agencies]

SINGAPORE - Maria Sharapova's hope of winning the WTA Finals is over, and her chance of taking the year-end No 1 ranking also came to an end.

Sharapova needed to beat Agnieszka Radwanska in straight sets on Friday to have any chance of progressing in the tournament, and she needed to win the title if she was to overtake Serena Williams at the top of the rankings.

Sharapova won the first set 7-5 but collapsed from a 5-1 lead in the second set and lost it in a tiebreak.