Button says he's even stronger in 2010

The new McLaren driver came through a difficult second half to last season to capture the crown in Brazil and, after admitting that he and his then Brawn GP team were too conservative in the way they went about trying to win, he says the lessons have been taken on board as he goes up against Lewis Hamilton this year.

"Because we were in such a position of leading the championship by quite a few points, we were too cautious," Button admitted on the main stage at the AUTOSPORT International Show. "We didn't want anything to go wrong.

"We were too cautious for the situation, although you can say too cautious and we still ended up winning the championship. I think we should have been a little bit more aggressive with our strategy, and also myself, I should have been more aggressive.

"It was a position I had never been in before. It was something I really learned through the season, and it is amazing that you learn so much when you are fighting for a championship - a championship that is so important to you. So it was a very up and down season, and when we got to Brazil, and also a couple of races before Brazil, we realised we started to need to get aggressive again and we really had to fight for this."

He added: "It wasn't just going to come to us. The thing is there was some negative publicity for a couple of races, but we never forgot that we had such a lead in the championship. We had a 14 point lead, and that was the worst it ever got before I won the championship, which is massive.

"The last three years have been won by one or two points, so it was a very strange position to be in knowing you had to be a little conservative and maybe when you are conservative you go too far. It is all learning curve, and you learn so much when you are in that position, and it means I come back this year so much stronger as an individual - not just as a driver."

Button has reiterated his stance that the decision to move to McLaren was fuelled by the fact that he wanted a new challenge in his career. And he says the change of scene has left him hugely motivated for the forthcoming season.

"It is an interesting one because people always say that after you win the world championship, are you really that hungry to achieve that again?" he said.

"I have been working for 21 years to achieve my goal - but yes, I am massively hungry. When I won the world championship in Brazil I was looking for something else. I thought I have achieved what I set out to do, but what do I do now? It is a very strange situation to be in, because you should enjoy the moment but it is very, very difficult to because you are always thinking too far ahead that you have to be careful of.

"I knew that moving to a new team and moving to Vodafone McLaren Mercedes would be a real challenge for me, and racing alongside Lewis, but it is a challenge I am so excited about. I am putting so much effort into making this work. This is the most important thing for me at the moment."

He added: "Winning the championship with Brawn was great, because we worked so hard for it over many, many years. But now to race for McLaren, a team that has so much history and has achieved so much in F1, is a real privilege for me.

"And working alongside Lewis, the guy has achieved so much in the sport in such a limited time, he has had some massive ups and downs, and it is my career squashed into two or three years. So, we have a lot of experience there and if we work together we will build a phenomenal race car and have a very good season."