The Spaniard, 26, came off his Honda at turn seven in Buriram and slid across the track as his bike flipped behind him.

Marquez was taken to hospital and had scans but was declared fit for the second practice session.

“We were lucky today – he’s OK,” Honda team boss Alberto Puig said.

“Marquez went to the hospital to check everything, they did an MRI and everything looks fine.

“He had some contusions in the back and also in the leg, and also here in the hip a little bit, but nothing to be worried about.”

Defending champion Marquez, who leads the standings by 98 points, can win the championship if he picks up at least two points more than nearest rival Andrea Dovizioso in Thailand.