Medical checks have revealed that Loris Capirossi is suffering from inflammation of the right shoulder.
The new Pramac Ducati rider has experienced pain since January and will now do all he can to be as fit as possible for round three of the world championship, at Estoril from April 29-May 1.
"I have to say that the check-ups I went through were positive,” said Capirossi.
“[On Wednesday] I had the artroscan, which showed that tendon and muscle have reported a injury. Fortunately there is nothing broken.
“Now I will work hard, twice a day, trying to get off the inflammation. I want to heal at all costs, for Estoril I hope to reach at least 80-85% of physical condition.”
Capirossi scored his first Pramac points with eleventh in last Sunday's wet Spanish MotoGP.
Fellow MotoGP riders Valentino Rossi, Dani Pedrosa and Cal Crutchlow are also recovering from some form of shoulder injury.
Pedrosa has used the longer than expected break between rounds two and three, following the postponement of the Japanese round, to undergo corrective surgery while Crutchlow is reported to have had an unrelated arm-pump operation.