Instead the Liquigas leader for the Tour of Flanders - same as in La Panne - is Luca Paolini, third recently in Milan-Sanremo.
"Doctors have told me that the tendon behind my left knee has a split in it. My main hamstring muscle has been compensating for it and I was close to tearing this from the bone. Luckily we caught it in time and I now have a month of recuperation ahead of me," the Wales-based Swede told cyclingnews.com.
Backstedt crashed in the Challenge Illes Baleares in February. He raced Tirreno-Adriatico with an inflamed tendon, but was forced to quit Milan-Sanremo after 200km.
Di Luca reclaims pink jersey
"I prepared so well for this season, I was lighter, fitter and stronger than I have ever been in my career. I have done it once this year, I can do it again! I will rest and gradually build back up to be competitive for the Tour de France and the second half of the season," Backstedt added.
Liquigas' squad for De Panne and Flanders: Michael Albasini, Daniele Colli, Alberto Curtolo, Mauro Da Dalto, Marco Milesi, Luca Paolini, Marco Righetto and Stefano Zanini.
DI LUCA: ALL EYES ON ITALY
"This year I'm focusing on the Giro d'Italia," inaugural Pro Tour winner Di Luca told his official website, indicating that he would not be looking to replicate his wins from last year in the Ardennaise classics.
In addition to Di Luca and Garzelli, the Liquigas' squad for the GP Indurain and Basque Tour will feature Dario Cioni, Vladimir Miholjevic, Matej Mugerli, Andrea Noè, Alessandro Spezialetti, and Charly Wegelius.
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