World champion Valentino Rossi has underlined his singular skill when he erased a 10 second penalty to win his third successive Australian Motorcycle Grand Prix.

He beat home fellow Italian Loris Capirossi (Ducati) and his young American Honda teammate Nicky Hayden, who snared his first podium.

Rossi was penalised in the confusion that followed a sickening crash by Ducati's Troy Bayliss which left the Australian unconscious on the in-field after just three laps.

Shocked when he learnt of the decision, Rossi determined to fight back and as a result described the race as "maybe the most exciting" he had contested.

"It's the first time I have raced at 100 per cent from the first lap to the last lap," he said.

Knowing he had to make up 10 seconds, Rossi roared off on his own private mission, crossing the line 15 seconds ahead of Capirossi - but five seconds in front on corrected time.

The drama begun when Italian Marco Melandri clipped Bayliss' Ducati, tipping him off onto his head and sending him tumbling into the grass.

Bayliss was later treated for concussion and bruising and taken to hospital for precautionary checks.

Rossi then passed Melandri under a yellow caution flag on lap five, but later claimed he didn't see it.

The Honda star lost his win in the British Grand Prix at Donington this year and was relegated to third place when he was also penalised for a yellow flag infringement - but in that race the penalty was imposed after the race ended.

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