If Sergio Perez has to sit out a third consecutive race, Pedro de la Rosa will occupy his Sauber seat.
Mexican Perez, 21, withdrew ill from his seat after initial Friday practice in Canada, two weeks after suffering concussion in a Monaco qualifying crash.
Sauber's managing director Monisha Kaltenborn on Thursday said the rookie is currently training in his native country.
"He is doing very well. We see no reason why he shouldn't drive in Valencia," she told Germany's motorsport-total.com, referring to next weekend's European grand prix.
Sauber's technical boss James Key, meanwhile, confirmed that if Perez is not fit enough for the streets of the Spanish port city, then Spaniard de la Rosa will occupy the seat.
We see no reason why he shouldn't drive in Valencia
"He did a great job for us," confirmed the Briton, referring to the 40-year-old McLaren reserve driver's race at short notice in Montreal.
Speaking to the Spanish press on Thursday, the country's motor racing president Carlos Gracia hoped de la Rosa will be in the Sauber cockpit next weekend, "without wishing ill on anyone".