BEIJING -- Dinara Safina was beaten 7-5, 7-6 (5) by local wild card entrant Zhang Shuai in the China Open second round, a shock defeat that could lead to the Russian's No. 1 ranking passing to Serena Williams.
The WTA reported that the upset victory late Monday made No. 226 Zhang the lowest-ranked woman ever to defeat a world No. 1.
Having lost the first set to the 20-year-old Zhang, Safina found herself 5-4 behind in the second. She rallied to force the tiebreak but with the crowd and momentum behind the local player.
Based on pre-tournament calculations, Safina would lose her No. 1 ranking to Serena Williams if she finished behind the American in China. Serena Williams won her first-round match Saturday against Estonia's Kaia Kanepi and next faces Russian Ekaterina Makarova on Tuesday.
The latest defeat comes a week after Safina was knocked out of the second round of the Toray Pan Pacific Open by 18-year-old qualifier Chang Kai-chen from Taiwan.
"I'm just having some bad losses right now. So many matches that are very close, ones that I should win, having set points or match points every time," Safina said in a post-match statement. "It's very disappointing. I would like to take some break now, and I'm very upset with myself."
Zhang said close losses in the past to high-ranking players gave her confidence that she could win at their level.
"I woke up this morning feeling really excited but didn't do any special preparation and never expected to win the match," she said.
However, Safina, who racked up 13 double-faults, was also "not in the best condition and made too many errors," Zhang said. Safina, who had begun shouting and growing visibly more distraught toward the end of the match, did not speak to reporters.
Her fellow Russian Pavlyuchenkova got dropped the first set against Venus Williams, a week after beating her in Tokyo.
But she won the second and held off the scrambling American in the third.
"She played really well. Sometimes I just made errors too soon in the point," said Williams, who made 12 double faults.
Asked if there was something about the Russian's game that she found difficult to handle, Williams declined to analyze.
"She plays well against everyone she plays and I think I usually do too," Williams said.
Pavlyuchenkova said Williams was more determined this week.
"She started actually way aggressive today especially the first set. She was playing much better, she was already preparing for this match more ... she wanted to kill me I guess," she said with a smile.
"I was happy overall with the way I played. It's just that I thought I could finish the job earlier. It was a little bit frustrating the way I was losing some points in the second set," No. 4-ranked Djokovic said. "That's the first round. You have to get used to the ups and downs a little bit and hopefully the next match will be more consistent and I'll be able to play my best."