Argentina's Juan Martin Del Potro may miss the French Open after picking up an injury to his left hip playing in the Madrid Masters tournament last week.
The 2009 US Open champion, who has only just returned to action after being sidelined for months with a serious wrist injury, flew home to Argentina for treatment. Medical tests showed that he had torn a muscle in the hip area.
"At this stage I do not know how long I will be unable to play but it is unlikely I will be fit enough im time for Roland Garros," Del Potro said in a statement.
The year's second Grand Slam event gets unerway in Paris on May 22.