BEIJING, (Reuters) – Serena Williams made a stuttering  start to her bid to topple Dinara Safina from the world number  one spot with an error-strewn 7-5 6-4 win over Estonian Kaia  Kanepi in the first round of the China Open yesterday.

Safina, who must at least match Williams’s progress over the  next week in Beijing to retain the number one ranking, was  equally unconvincing in her 6-4 6-4 victory over Italian Roberta  Vinci earlier in the day.

Williams missed last week’s Pan Pacific Open with knee and  toe injuries and looked far from her best in her first singles  match since her rant at a lineswoman at the U.S. Open last  month.

“I’m definitely not at 100 percent but I’m just fighting and  trying to do the best I can,” Williams told reporters.

“It wasn’t easy but I felt like I was hitting a clean ball.  She’s a really good player, she always plays tough.”

The Australian Open and Wimbledon champion made nine  unforced errors in the 83-minute encounter against the  big-hitting Kanepi, who broke the second seed three times.

Williams, though, always looked to have the edge on the big  points and reached the second round of the $6.6-million event  with a fifth break of serve when Kanepi went long, keeping alive  the American’s hopes of reclaiming the top ranking.

“I would love to be number one,” added 11-times grand slam  winner Williams. “But I also want to pay the price to be number  one. It’ll come eventually. And if not, I’ll just keep trying.”

Early breaks

Top seed Safina’s victory over 59th-ranked Vinci was  certainly an improvement on her first-round loss to Taiwanese  qualifier Chang Kai-chen at the Pan Pacific Open last week but  was by no means commanding.

Broken early in both sets, Safina immediately evened up  matters with breaks of her own but was then forced to scrap it  out with the dogged Italian to claim victory.

“I’m satisfied with the match but there is still room to  improve my game,” said the 23-year-old Russian.

“I’m not thinking about (the ranking). I just think about  the game. I think I am the 16th, 17th in the world to reach  number one so it doesn’t matter when you achieve it.”

Fifth seed Caroline Wozniacki of Denmark suffered a  first-round upset, crashing out 6-7 7-6 6-0 to Spain’s Maria  Jose Martinez Sanchez.

Fourth seed Elena Dementieva, returning to the scene of her  Olympic triumph last year, had no such problems with her opening  match and dispensed with Germany’s Anna-Lena Groenefeld 6-4 6-0  in just over an hour.

Dementieva’s sixth-seeded fellow Russian Svetlana Kuznetsova  started the day by damaging hopes of a first local champion with  a 7-6 7-5 defeat of China’s number two Zheng Jie.