The Serb pulled out of the Madrid Open earlier this month with the recurring injury, which worsened after her country's Fed Cup win over Spain in April. The 21-year-old from Belgrade vowed to be fit for her French defense but coach Craig Cardon was recently quoted by the tennis channel website (www.tennischannel.com) as saying her appearance there was doubtful.

"I am not sure she is even going to be able to play at the French Open because of this knee injury," Cardon said, although he added: "I know her confidence is still pretty high and her level of play is good enough for Ana to win it again."

Even if she plays, the world number eight will need more than confidence to retain her Roland Garros crown after plummeting down the WTA rankings from the number one spot she grabbed after taking last year's title. She has since won only the Linz Open last October. After another dip in form she was knocked out by unheralded Russian Alisa Kleybanova in the third round of the Australian Open. If she does miss the French open, Ivanovic will almost certainly drop out of the top 10 a severe setback after becoming the first Serb to climb to the WTA summit.

JANKOVIC DESPAIR

Fellow Serb Jelena Jankovic, who ended 2008 as the world number one without ever winning a grand slam title, has had to battle her own problems in a disappointing season. Her lightning reflexes, stamina and speed around the court, qualities that powered her consistent rise in 2008, disappeared after she gained weight during the Christmas break after building up extra muscle and strength.

Jankovic made a fourth-round exit from the Australian Open and her Madrid quarter-final defeat by Swiss Patty Schnyder has made her drop to fifth in the WTA rankings.