The unusual accident occurred when Rossi, testing alongside a full line-up of MotoGP rivals, was suddenly flicked from his new M1 on the exit of the tight first-turn hairpin, shortly after midday.

Despite being thrown into the air, the Italian got back onto his feet unaided before bump starting his bike and returning to the pits.

Rossi, who is aiming take his new Bridgestone-shod M1 to a sixth premier-class world crown - after two successive title defeats - went on to finish the day in sixth position, 1.1secs behind fastest man Randy de Puniet.

"It feels good to be back on the bike after the winter break, and me and all my team are feeling very motivated about the task ahead," began Rossi. "I still have some pain in my hand [from his Valencia accident] but I had it checked out again last week and the fracture is okay, so I know it's not a problem to ride.

"Today we continued where we left off with Bridgestone and it seems we're making good progress, we did many laps with the same tyre and I'm pleased with things so far.

"Unfortunately I had a crash today; I was on an out lap and maybe I pushed a little bit too hard, too soon, with not enough temperature in the tyre and I lost the front. Luckily I was not hurt, my hand is okay and I was able to continue with the day's work!

"As well as tyres we tried a new-spec engine and I was quite pleased with this, as well as with some new electronics. The surface wasn't good today and it wasn't possible to go so fast but I hope tomorrow it will improve and we will be able to keep improving in all areas," he added.

The 'new-spec' engine Rossi referred to features pneumatic valves, something Yamaha were thought to have abandoned after their setbacks with that type of engine during the second half of last season...