MotoGP champion Marc Marquez 'ok' after serious crash at Indonesian Grand Prix

Marc Marquez fractured right arm in the 2020 season-opening Spanish Grand Prix in Jerez last July. Javier Soriano/AFP

Honda's Marc Marquez took to social media to reassure his fans he was all-right after suffering a concussion in a shocking crash during the warm-up session that ruled him out of Sunday's Indonesian Grand Prix.

Marquez suffered a high side on turn seven that launched him into the air and the six-time MotoGP champion landed heavily on his side. He took a whack to his head but avoided serious injury as the cartwheeling bike missed colliding with him.

Marquez was visibly dazed and hospital checks revealed the Spaniard had suffered a concussion, with doctors declaring him unfit to race.

"I'm OK after the big crash I had this morning. For precaution and to not take any more risks, we decided to not race at the Indonesian GP," Marquez wrote on Twitter.

"I want to thank all the MotoGP medical team and the Mataram Hospital for the treatment received."

The 29-year-old crashed twice during qualifying on Saturday. He was due to start from 14th on the grid after moving up a spot following Franco Morbidelli's three-place grid penalty.

Marquez also had problems with double vision towards the end of the 2021 season following a concussion he suffered in a training crash. The Spaniard said before the 2022 season that doctors had advised him not to continue racing.

Organisers reduced the race from 27 laps to 20 due to tyre safety concerns caused by extreme heat at the Mandalika track and the race start was delayed due to torrential rain.

KTM rider Miguel Oliveira put on a wet-weather masterclass and held off world champion Fabio Quartararo of Yamaha to win Indonesia's first grand prix since 1997.