Brussels - The injury worries continues for fragile world number one Justine Henin, who has withdrawn from next week's WTA green clay event in Charleston with more knee problems.
The Belgian limped out in a 6-2, 6-0 quarter-final loss to Serena Williams last week in Miami and has been saying that the knee which has bothered her for weeks is still not at 100 per cent.
Henin is next expected to play in Berlin from May 5 in a late start to the defence of a fourth Roland Garros title. "She does not want to endanger her clay court season," read a statement on the Belgian's website.
Henin has played in six events so far this WTA season, winning in Sydney and Antwerp. (dpa)

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