Jankovic was trailing 1-0 in the opening set of her singles match against France's Tatiana Golovin when she pulled her right hamstring. That forced her to retire and give France a 1-0 lead in the match.

While Djokovic was beating Arnaud Clement 6-3, 6-3 in the men's singles to level the match, an MRI scan of Jankovic's upper right leg showed that she had not torn her hamstring. She decided to play the mixed doubles.

The No. 3-ranked Jankovic limped during the final match and couldn't go after wide shots at the back of the court. She also had her upper right leg taped, and left the court several times during the match to have the strapping replaced.

But she seemed to improve later in the match, and Serbia won 5-7, 6-4 and 10-4 in the match tiebreaker.

"I had such a motivation to win this match," Jankovic said. "I have to thank Novak for running all over the court to help me."

Djokovic praised Jankovic for her decision to continue playing.

"I was trying to run all over the place but even (though) she played on one foot we have to give her credit," Djokovic said. "She played a great match. If there wasn't good hands and good feeling from my experienced partner I don't think we would have won."

The win left Serbia with a 2-0 record while France dropped to 1-1. Serbia, which has a strong chance of advancing to Friday's final, plays Argentina in its last round-robin match Thursday while France plays Taiwan.

Taiwan beat Argentina 3-0 later Wednesday. Hsieh Su-wei gave Taiwan a 1-0 lead with a 3-6, 7-6 (2), 7-5 win over Gisela Dulko and Lu Yen-hsun clinched it when he beat Juan Ignacio Chela 6-3, 6-4.

Hsieh and Lu beat Dulko and Chela 3-6, 6-4, 10-4 (match tiebreaker) in mixed doubles.

Taiwan improved to 1-1 and Argentina is 0-2.