Heroic Wozniacki seals second win at WTA Championships

CAROLINE Wozniacki played through the pain barrier to defeat Vera Zvonareva and maintain her 100 per cent start to the WTA Championships.

HEROIC: Caroline Wozniacki, pictured here at the US Open, suffered repeated cramping on her way to victory over Vera Zvonareva (Getty Images)

Wozniacki came from a set down in her opening White Group match to overhaul Victoria Azarenka, while Russian Zvonareva, originally a reserve in Doha, stepped in after Dinara Safina withdrew just two games into her first match.

And it was US Open finalist Wozniacki who emerged as 6-0, 6-7, 6-4 victor despite repeated treatment for a hamstring injury.

Wozniacki - seeded fourth in Qatar - was in crushing form in the opening set but Zvonareva - who was given less than 24 hours to prepare for her WTA Championship debut - rallied to ensure it was not all one-way traffic in the second.

Wozniacki looked to have made the decisive breakthrough to hold a 5-2 lead but Olympic bronze medallist Zvonareva hit back to level 5-5.

And Zvonareva saved a match point on serve two games later to force the set to a tie-break before levelling proceedings.

Wozniacki - who became the first Danish woman to reach a grand slam final - had to call the trainer on throughout the final set but still managed to break Zvonareva, who herself needed treatment for a heavy nosebleed in the second set.

And serving for the match, Wozniacki collapsed in agony and unable to receive treatment - but got to her feet to close out a match which lasted almost three hours.