Image 1 of 4 Tom Boonen (Omega Pharma QuickStep) crashes out of the Tour of Flanders (Image credit: Bettini Photo) Image 2 of 4 Tom Boonen (Omega Pharma QuickStep) crashes out of the Tour of Flanders (Image credit: Bettini Photo) Image 3 of 4 Belgian champion Tom Boonen (Omega Pharma-Quickstep) was a pre-race favorite at the Grand Prix de Wallonie. (Image credit: Isabelle Duchesne) Image 4 of 4 Tour of Flanders favourites Fabian Cancellara, left, and Tom Boonen chat on the start line. (Image credit: Photopress.be)

Tom Boonen is still recovering from injuries suffered in a crash at the the Tour of Flanders and will not ride the Tour of California, which starts next week. Omega Pharma-QuickStep team manager Patrick Lefevere confirmed the non-participation.

"We find that he has not recovered enough. He is still suffering from the knee which he had surgery on and also his thigh and his back hurt,” Lefevere told sporza.be. “This should be dealt with first, the rest will follow it.

"Tom trains already, but not yet fully. The Tour of California this year is also very difficult.”

The former World Champion is expected to return to the Tour of Belgium, May 22-26. Lefevere and Boonen will meet on Wednesday to discuss the further season.

Boonen had gone into the Tour of Flanders as one of the favourites, but crashed out after only 19 km,when he hit a road sign, injuring his left knee, hip and elbow and also breaking a rib.