BEIJING (AP) -- Serena Williams was knocked out of the China Open on Thursday, losing to Nadia Petrova of Russia 6-4, 3-6, 7-6 (5) only days before regaining the No. 1 ranking.Williams, who will take over the top spot in the rankings from Dinara Safina on Monday, looked sluggish in the first set before recovering in the second. Neither player was able to earn a break in the third set.
"I don't feel like I ever got into high gear," Williams said. "I ran into a girl today who has never played so good in her life."
WIMBLEDON, England (AP) -- When 
