The second-seeded Williams was broken twice while struggling through a windy second set. At 5-3 with Zakopalova serving, she had five match points but couldn’t close it out.
Jelena Jankovic dominated her opponent before a 2-hour rain delay, and then did well enough after it to advance to the second round by beating Petra Cetkovska of the Czech Republic 6-2, 6-3.
The fifth-seeded Jankovic was leading 4-1 when the rain started at Roland Garros. She quickly closed out the first set when play resumed and continued to play well on Cetkovska’s serve in the second but was broken twice on her own.
“I was controlling the points ... but then we had to stop because of the rain,” Jankovic said. “I felt a little bit slow after the rain delay.”
While serving for the match, Jankovic again struggled and was forced to save break points before finally winning.
“The serve was all right. I didn’t go for too much,” said Jankovic, who added the balls were heavier than usual because of the wet weather. “I just tried to have a high percentage.”
Jankovic finished last season as the top-ranked player on the women’s tour, but the 24-year-old Serb is still looking to win her first Grand Slam singles title after losing in the final of last year’s U.S. Open.
Seventh-seeded Svetlana Kuznetsova also advanced, defeating Claire Feuerstein of France 6-1, 6-4. The 2004 U.S. Open champion also dominated before the rain started falling, leading 5-1.
Later Tuesday, second-seeded Serena Williams was playing on Court Suzanne Lenglen.
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