Kim Clijsters will miss the Nasdaq 100 Open Masters Series in Miami with a wrist injury.
Clijsters could be out for a month
The world number two has torn a tendon in her left wrist and has been fitted with a brace to treat the problem.
"I cannot sleep because of the pain," Clijsters told her official website. "I can't even wash my hair."
The Belgian picked up the injury in a 6-1 6-3 win over Angelika Roesch at the Pacific Life Open and had to retire from the tournament as a result.
"I can't even manage to type in my diary," she said.
"I am trying to keep my form and fitness, but running with my brace on isn't easy. I have to be careful not to slip of course."
Clijsters has pencilled in the Fed Cup on 24-25 April for her return.
"It will become difficult to be strong for the Fed Cup," she added. "At this moment, chances that I will play the Fed Cup are still higher than the ones of not playing."