Arvidsson wins as Zheng retires in Sofia

SOFIA, Bulgaria (AP) - Sofia Arvidsson of Sweden secured victory without finishing the first set when Zheng Jie of China retired at 5-1 in the season-ending Tournament of Champions on Friday.

On the last day of the event's group stage, Arvidsson replaced Maria Kirilenko, who pulled out of the competition on Thursday with an upper respiratory illness. Arvidsson and Zheng had no chance of advancing to the semifinals.

In the second group match, Russia's Nadia Petrova rallied from a game down to beat Tsvetana Pironkova of Bulgaria 5-7, 6-1, 6-3 - a victory that earned her first place in the Sredets Group.

In Group Serdika, Taiwan's Su-wei Hsieh will play Slovakia's Daniela Hantuchova in the last match of the day, though neither can advance after Caroline Wozniacki and Italy's Roberta Vinci secured their berths for the semis.

In the semifinals on Saturday, top-seeded Wozniacki will play Pironkova, while Petrova will face Vinci.

"I need to recover fast because it will be a challenging game tomorrow. Roberta (Vinci) is always giving her opponent a hard time with her slice,'' Petrova said.