(Reuters) - MotoGP champion Marc Marquez had fresh surgery on Monday to replace a damaged titanium plate inserted after he broke his arm in the July 19 season-opening race in Spain, making him uncertain for Sunday's Czech Grand Prix.
His Repsol Honda team said the Spaniard will stay in hospital in Barcelona for 48 hours before being discharged.
"Marc Marquez underwent surgery 13 days ago and today he returned to the operating room," doctor Xavier Mir said in the statement.
"The first operation was successful, what was not expected was that the plate was insufficient.
"An accumulation of stress in the operated area has caused the plate to suffer some damage, so today the titanium plate has been removed and replaced by a new fixation. The rider has not felt pain during this period."
The Czech Grand Prix is in Brno, with Petronas Yahama's French rider Fabio Quartararo going for a third win in three races.
Marquez attempted to return for the second race of the season in Jerez on July 26 but withdrew without qualifying on the Saturday.
(Reporting by Alan Baldwin in London, editing by Pritha Sarkar)