Maria Sharapova went out of the WTA Finals and missed her chance to end the year as world number one despite a win over Agnieszka Radwanska in Singapore.
The Russian could have kept alive her hopes with a straight-sets win in her final group match, but missed three match points in the second set.
Sharapova went on to win 7-5 6-7 (4-7) 6-2, but the result means Serena Williams retains the top ranking.
