Greater Noida: An emotional Sebastian Vettel Sunday admitted it was tough to deal with being booed this season -- but said he found the perfect riposte by winning the world championship once again.
The likeable Vettel, 26, said booing and jeering which greeted his wins in Belgium, Italy and Singapore, as he took control of the season, had come as a shock.
But Vettel, who won the Indian Grand Prix to seal his fourth successive world title, said he was glad he had managed to answer his critics with his performances on the track.
"To be booed when I had not done anything wrong was hard, but I think I answered the things on the track which I am very pleased about," he said.
"I don't blame the people who booed me. It does not feel great. In fact one guy wrote a letter and apologised that he was booing. He felt bad about it.
"We are all part of the sport. If some people have passion for Ferrari for some reason, it's all right. It is not necessarily my fault. I am mature enough to understand that."
The booing, which Vettel has blamed on a small section of disgruntled Ferrari fans, has been an unfortunate feature of the season.
Vettel first attracted criticism when he ignored team orders and overtook Red Bull stablemate Mark Webber to win the Malaysian Grand Prix.
And while he has been putting together a six-race winning streak to clinch the championship, Vettel also heard complaints that he was making the sport boring.
The young German was anything but staid in his celebrations at Buddh International Circuit, where he span doughnuts in his Red Bull before bowing in front of the car in mock worship.
Vettel, who was also lifted onto the shoulders of Nico Rosberg and Romain Grosjean, who placed second and third, called it simply the "best day of his life".
"I am speechless," a visibly drained Vettel said. "I spent ages thinking what to say, there is so much you want to say at a time like this."
"I am overwhelmed. It is the best day of my life so far."
He also paid warm tribute to his Red Bull team, who have now won both the drivers' and constructors' title for four seasons in a row.
"The guys are working very hard behind the scenes. And when you see their paychecks, you would be surprised. It would seem they were working at McDonald's," said Vettel.
He added: "When I started to race, Formula One seemed so far away, but there are so many people I have to thank along the way from karting to here," he said.
"I was taught so many things and I have always tried to listen, but to come out on top of this incredibly talented field is amazing.
"I am not old yet but I am getting older and maybe I am not grasping it yet. Maybe in 10 years' time I will look back and realise the enormity."