Former world number one Victoria Azarenka pulled out of the Madrid and Rome WTA events on Saturday with a left foot injury which could put her French Open hopes in doubt.
The Belarus star has not played since a second round loss to Lauren Davis at Indian Wells in the first week of March.
The 24-year-old announced on Facebook that she would be forced to miss the Madrid and Rome events in May, both crucial warm-up tournaments ahead of the French Open, the second Grand Slam of the season, which gets under way on May 25.
"My recovery is still going on but I am still not fit enough to play these two events," said Azarenka.
She has only played three tournaments in 2014, making the final in Brisbane, exiting in the quarter-finals of the Australian Open before her early loss in California.
"I am working hard to get fit again. Will be in touch soon," she added.