MADRID, Nov. 11 (Xinhua) -- Belgian tennis player Justine Henin, the world's number one, retained her WTA Championship title here on Sunday with a 2-1 victory over Russia's Maria Sharapova.

The 5-7, 7-5 and 6-3 victory, which took nearly three hours and 24 minutes, caps a nearly perfect season for Henin, who has won 10 Grand Slams including France's Ronald Garros and the US Open.

Henin has now gone 25 matches without a loss. The last to defeat her was France's Marion Bartoli in Wimbledon in 2006.

The final promised to be exciting and was no disappointment. Both Sharapova and Henin had won every match on the way to final.

It was a grudge match from Sharapova, who was knocked out of the competition at the semi-final stage in 2006 by Henin.

Sharapova, a Siberian, won the first set, but Henin's mental strength eventually turned her into one more notch on Henin's belt.