Hamilton victory investigated.

Lewis Hamilton's win in the Japanese Grand Prix might have been straight-forward on the road, but was apparently less so as stewards deliberated long into the Fuji night.

According to Spain's Marca newspaper, the Briton's tactics behind the safety car were called into question, particularly after its second appearance, when Sebastian Vettel and Mark Webber collided.

The young German pointed to Hamilton's aggressive accelerating and braking - used to warm tyres and brakes - as a contributory factor to the incident, suggesting that he had been distracted by the sight of Hamilton slowing heavily and not noticing his own proximity to the back of Webber's car. The incident took the two Red Bull-backed cars out of potential podium finishes.

"With the final safety car, I was behind Lewis and Mark and, exiting Turn 13, I looked to the right and saw Lewis going really slowly," he said, "I don't know why, but I thought he had a problem, [when] probably he was heating his brakes. Then, by the time I looked forward again, I was already in the back of Mark's car as I think he had also reacted to Lewis."

Hamilton had employed similar tactics at the 'start' of the race on lap 19, when trying to get the jump on McLaren team-mate and title rival Fernando Alonso. On one occasion, the Briton backed off so much that Alonso had to check up suddenly to avoid passing him, but the stewards decided not to take any action against the rookie, who now heads into the penultimate round of the season with a twelve-point lead over his team-mate.