German No.3 Andrea Petkovic has been forced to withdraw from The Championships 2012 due to a continuing right ankle injury.
"Unfortunately, I will not be able to return in time for Wimbledon this year," Petkovic commented. "While this is another setback in my return, I will continue to work hard on getting back on court as soon as possible."
The German, who reached a career-high ranking of world No.9 in October 2011, reached three Grand Slam quarter-finals last year, at the Australian Open, French Open and US Open, and the third round at The Championships.
Petkovic has been replaced in the main draw by Bojana Jovanovski of Serbia.
Agnes Szavay and Kaia Kanepi have also withdrawn from the Ladies' Singles, with a back injury and foot injury respectively. Szavay will be replaced by Lesia Tsurenko, and Kanepi by Heather Watson.
Pablo Cuevas has withdrawn from the Gentlemen's Singles due to surgery. He will be replaced by Vasek Pospisil of Canada.