Federer was to open his draw at the Gerry Weber Open, a tournament he's won five times in six years, on Wednesday but pulled out with an apology to the "tournament organizers, my competitors and my fans in Germany."
"I only hope they will understand that I still feel emotionally overwhelmed and exhausted by the incredible events of the past few days," Federer said on his Web site. "It is hard for me to admit but I simply cannot imagine giving my best effort in another tournament right away and I don't want to risk injury if I am not 100 percent prepared. I need to rest and recuperate."
Federer, ranked No. 2 in the world, on Sunday became the sixth man to complete the career Grand slam with a straight-set win in the final of the French Open. It was his 14th major tournament title, tying him with record-holding Pete Sampras.
The grass-court Gerry Weber Open is seen as a key tuneup ahead of the Wimbledon Championships, which begin June 22.