McLaren will test Juan Pablo Montoya in their F1 simulator before deciding whether he can make his comeback at next month's Spanish Grand Prix.
Montoya may not be fully race-fit in time to compete in Spain
Montoya suffered a hairline fracture of the shoulder in a fall playing tennis last month and will have missed two grands prix before Barcelona on 8 May.
McLaren boss Ron Dennis said: "The bone has healed quite well but he's had quite a bit of muscle wastage.
"We will determine from his simulator performance whether he's fit to race."
Montoya is scheduled to have more scans, and Dennis added: "That muscle strength has got to come back."
Austria's Alexander Wurz is taking Montoya's place this weekend Imola, the fourth race of the season.
His fellow McLaren test driver Pedro de la Rosa of Spain competed in Bahrain three weeks ago.
It will be Wurz's first race since the end of the 2000 season when he drove for Benetton.