Sebastian Vettel said clinching his fourth consecutive Formula 1 world championship left him speechless, as he wrapped up the 2013 crown with Indian Grand Prix victory.
Vettel's win at Buddh was his sixth grand prix victory in a row. The Red Bull man has not been defeated since the Hungarian GP before the summer break.
"I'm speechless. I crossed the line and I was empty," said Vettel.
"I took ages to think of something to say, and it's one of those moments you wish to say so many things but you can't. It's a pleasure to jump in the car and go out for the guys and give it all I have.
"The car was phenomenal today, it was phenomenal all season. I couldn't ask for more."
Vettel launched into a series of celebratory donuts on the main straight after the race, and admitted this gesture was unplanned.
"I hadn't really thought about it," he said. "Rocky [Guillaume Roquelin] my engineer called for the usual procedure and I thought, 'Not this time.' There are so many people in the main grandstand, I had to do it.
"Usually we are not allowed to but it felt so right."
The German said the championship and the reception in India were particularly rewarding given the perception that Red Bull had had a dominant car and the heckling he received on some podiums this year.
"It was not an easy season for sure, even though people from the outside got the idea that we had it in our hands for the last couple of races," said Vettel. "It was very difficult for me personally to receive boos even though I hadn't done anything wrong.
"To overcome that and give the right answer on the track and finally get the acceptance I think we are all looking for as racing drivers makes me very proud."