Fermin Aldeguer has not recovered from his injuries in time to make a return at next week's British Grand Prix, with World Superbike star Iker Lecuona replacing him at Gresini's MotoGP team.
The Spaniard suffered a fracture to a thoracic vertebra, T7, during practice for the Dutch Grand Prix at the end of June. The doctors opted for a conservative treatment, without surgery, with rest for a natural recovery.
Despite MotoGP's summer break offering him the chance to speed up the process, Aldeguer will not be fit to race at Silverstone on 8-9 August.
A Gresini statement read: "Fermin Aldeguer will not compete at Silverstone in the 12th round of the MotoGP World Championship.
"The Spanish rider will remain out of competition as a precaution. However, he has been medically cleared to resume training from August 15 onwards, and Team Gresini will welcome him back in Aragon in approximately one month's time.
"Iker Lecuona returns to the Gresini family this weekend at Silverstone, after replacing Alex Marquez in Hungary."
Lecuona, a rider for the factory Ducati team in WSBK, already took part in the Hungarian Grand Prix on 7 June with Gresini, although on that occasion he replaced an injured Marquez. The former Tech3 rider finished the Balaton Park race, his first in MotoGP in three years, in a remarkable seventh place.
Aldeguer's sophomore year in MotoGP got off to a poor start, with a serious injury to his left leg sustained in January keeping him away from the track for several races.
Then, he crashed during Assen practice, suffering damage to his vertebrae, which prevented him from continuing with the weekend. In addition, the Murcia-born rider also missed the following race in Germany, completing only eight of the first eleven grands prix of the season.
According to the statement, the Gresini team is confident that Aldguer will be able to resume activity and return to training in around two weeks, in order to make his comeback at the Aragon Grand Prix - which takes place over the weekend of 28-30 August 28-30.
