Six-times MotoGP champion Marc Marquez has had a third operation on his right arm to put in a new plate, his Repsol Honda team said in a statement on Thursday.
The Spaniard fractured his humerus in the season-opening Spanish Grand Prix in Jerez in July and had a second operation after damaging a plate in his arm while opening a window at home.
He ended up missing the rest of the season, failing to score a single point.
Honda said the latest surgery was due to the slow healing of the humerus "which has not improved with specific shock wave treatment."
The procedure lasted eight hours, they said, and was uneventful.
Honda did not say how long the Spaniard's recovery might take but motorsport.com suggested he could be out for six months, which would mean missing the start of next season.
The first race is in Qatar on March 28. (Reporting by Alan Baldwin in London, Editing by Himani Sarkar)