Jenson Button admits the next few months will be vital towards his 2013 title bid as he looks to "direct" McLaren's new car in the way he wants.
With Lewis Hamilton leaving McLaren for Mercedes and Sergio Perez taking his seat, Button has become the unofficial team leader at McLaren.
The Brit acknowledges that now that he has that role he can have a firmer say in what direction McLaren take with their MP4-28. And he intends taking full advantage of that.
"I still think we're going to have two drivers that want to win the World Championship," the 32-year-old told Sky Sports News.
"I don't think that changes - we're all here to do a job and we all think we can win the World Championship - but it is different [going into 2013].
"Lewis is going to be leaving this team [and], when you're team-mates with Lewis, you share the direction of the car, if you like.
"Now, with Lewis leaving, I have a couple of months to really direct the team into what I would like with the car before 'Checo' arrives.
"That's an important couple of months for me to really feel that I've got a good direction with the car, because Sergio is going to be quick.
"That's good, [as] you need a team-mate that's quick, and I think he's going to learn very quickly, which is very good for him."
Reflecting on this past season, which Button finished fifth in the Drivers' Championship. 93 points off the pace, the 2009 World Champ says he had hoped for better.
"In terms of the end result and the points, I'm not very happy but, in terms of what we've learnt this year, it's been really useful.
"In a way, it's been like a great 'testing' season because we've had great results [and] we've had bad results in terms of the whole team.
"We've learnt a lot and, in that period around Monaco and Canada, when I had some really bad races, we got a lot of information with the direction we took with the car, which was wrong, and it's been really useful for us for the rest of the year.
"I think we can take that forward to 2013."