Jenson Button would have lost a late sprint to the chequered flag in the Australian Grand Prix if the looming challenge of BMW-Sauber driver Robert Kubica had not been wrecked by Red Bull's Sebastian Vettel.

That was the claim made today by BMW-Sauber boss Mario Theissen who said Kubica was on course for victory because he was on hard tyres, offering greater grip, while Button was struggling as his set of soft tyres wore down.

But just three laps from home Kubica was rammed by Vettel. Both drivers continued, but they had sustained serious damage in the heavy collision and both hit the wall at the next corner.

Theissen said: "We are very confident Robert would have won the race. He was lapping about two seconds quicker than Button."

Kubica confirmed: "I was much quicker than Button, and catching him up."

Vettel paid for his mistake when race officials hit him with a 10-place grid penalty for next Sunday's Malaysian Grand Prix, and fined Red Bull £35,000 for allowing their driver to continue lapping slowly with one wheel hanging loose from where it had hit the barrier.

Straight after the original accident a contrite Vettel sent a radio message to his team, admitting: "I'm an idiot. I'm sorry. I'm very, very sorry."

Later, he said: "You always want to fight. Maybe I should have let Robert go and bring third back home, but that's life. I'm sorry to the team and also to Robert, as it didn't just mean the end of my race but also his."