Amelie Mauresmo could lose her world number one status this week after pulling out of the Kremlin Cup because of a thigh injury. The Frenchwoman sustained the injury during the final of the Porsche Grand Prix against Lindsay Davenport and retired after losing the first set 6-2.
"Amelie slightly pulled a thigh muscle so she is not going to Moscow," said her coach Loic Courteau.
Davenport will become number one if she reaches the quarter-finals in Moscow.
She trails Mauresmo by just 15 points in the world rankings.
And Courteau said a decision would be made at the end of the week whether Mauresmo would play in the Swisscom Challenge in Zurich, which starts on 18 October.
Meanwhile, three-time champion Magdalena Maleeva was beaten 5-7 6-4 6-4 by Russian wildcard Vera Douchevina in the first round.