[Rusty Backhand]

BEIJING, Sept 20 (Reuters) - Serena Williams fired a warning to Maria Sharapova on Tuesday, telling her she would only be satisfied when she had snatched her world number one ranking back from the Russian.

http://go.reuters.co.uk/newsArticle.jhtml?type=tennisNews&storyID=9701032&section=news&src=rss/uk/tennisNews