Sebastian Vettel insists he did not see Jenson Button in Suzuka start incident

Pole-winner Vettel made a slightly slow start and then eased across towards the faster-moving Button, who ran out of space and had to take to the grass before backing off and dropping to third behind McLaren team-mate Lewis Hamilton. Button recovered to win the race, while Vettel came home third and clinched the 2011 title.

Vettel said he apologised to Button after the race, insisting he had not seen him, but also joked that he had coped fine when edged towards the grass himself by Fernando Alonso as they battled for the Italian Grand Prix lead last month.

"Ask Fernando, I think Formula 1 cars can go on grass with two wheels..." Vettel said to television reporters.

"I didn't mean to push [Button] on the grass. Initially I thought I had a very good start, I knew that it wasn't perfect but I knew it was good because I was pulling away from Lewis.

"When I stop in my box, when the lights go off I can't see Jenson. The reference really, after I have done my bit, is Lewis. I thought maybe Jenson didn't have a good start because of the dirty side of the track, so I pointed to the right naturally - I think it's in all our blood when you are on pole to pull to the inside to make sure.

"And I saw him, saw that there wasn't much room and that he was a bit on the grass and had to obviously lift. But I spoke to him straight after the race and obviously there was no intention to put him in danger."

Button admitted it had been a very unnerving moment.

"I got a very good start, Seb didn't, and I think he realised immediately that he didn't get a good start and he started coming across," said Button.

"I was using as much KERS as I could to get up the inside and he kept coming, he kept coming and he kept coming. I thought in the end he was going to stop, because I was halfway alongside him.

"But he didn't stop, so I got onto the grass and then ended up backing out - I had to, because it would've been an almighty shunt into Turn 1.

"I was a bit surprised. He said that he didn't see me coming until he saw me backing out. And if that's the truth, then it's one of those things.

"I got out of there and I lost a place, which is disappointing, but in a way it's quite nice fighting your way through."

After the incident Button radioed his team to say Vettel ought to receive a penalty, but said that opinion had been expressed in the heat of the moment.

"That's how I felt at that time. Emotions were running high," Button said.

"I've spoken to Seb since and he's said he didn't see me until I backed out of it when I was on the grass. I hope that Seb doesn't lie, so I take his word for it. We're all tough on each other. It's difficult to find the limits.

"The important thing is that I beat him in the race and won the grand prix. But I want to say congratulations to him, he's driven a great year."