Jenson Button admits McLaren cannot afford anything but a "very clean" season if they want to end Sebastian Vettel's reign.
Having claimed the World title in 2009 with Brawn GP, Button moved over to McLaren but to date has failed to claim the ultimate triumph. Instead that honour has gone to Vettel.
The Red Bull racer has won three titles on the trot while Button's best was runner-up in 2011.
This season the Brit is determined to end the German's reign but concedes he needs an error-free season in order to launch a challenge.
"We [McLaren] haven't won the World Championship since 2008 and I haven't won it since 2009. It's four years and we want to get it back. We're going to do everything we can to do that," he told The Guardian.
"But I think everyone apart from Sebastian is probably saying the same thing. Fernando [Alonso] had a great year last year but didn't win the World Championship so Ferrari will be saying, 'This is an important year for us. It has been a long time.'
"Even if you win the first race, it doesn't mean you're going to win the World Championship, as I proved last year. It's about staying calm, focusing on the fine details especially because there aren't any regulation changes. You can't slip up through the year.
"We can't have a year like last year, in terms of reliability issues, mistakes, having an inconsistent season. Everything has to go to plan, to be smooth, because I don't think people are going to be making big mistakes.
"It has to be a very clean season, and to do that we have to stay relaxed, really pull together, and focus on every single detail about the car and the race weekend. We can't slip up."
As such the 33-year-old has been working hard on his fitness and took part in a half-marathon in Cannes on the south coast of France late last month. He reportedly recorded a time of 1:19.
"I don't know if it's the same for every driver but you do put in the extra effort through the winter, and because I've been training for so many years now, it does all add up.
"The amount of hours I do now I wouldn't have been able to do four years ago. Physically it would have been too demanding on the body, but my body is used to it now so you can put more time into it.
"But then it's not just about the physical training over the winter, its about the mental training and putting yourself through all sorts.
"I did a half-marathon in Cannes recently. It was zero degrees and I did an hour and 19 minutes which I was chuffed to bits with.
"But it was one of the most painful things I've ever done. Two days after I was still hurting from it.
"In putting myself through that pain, especially the last 20 minutes, the way I got to the end was to think about the first race of the season.
"I thought about being mentally and physically prepared, not feeling the pressure, feeling comfortable within myself and within the team.
"That's what kept me going. When I got to the end the strength I'd gained through doing it, mentally and physically, will help me so much when I arrive at the first race.
"Maybe that's why the first race is normally pretty good for us."
That first race takes place at the Albert Park circuit in Melbourne, a circuit where Button has claimed a hat-trick of victories including 2009 when he went on to win the World title.
"Australia is such a special race for all of us. You get to the end of the year every year in Brazil and there are not many people smiling in the paddock. But at the first race it's all fresh, new, exciting. Every single person in the paddock is smiling.
"It's a great place to start the season - beautiful setting, the Aussies are big fans of sport in general. I've obviously had a good car to achieve what I have but we won in 2010, when we didn't have such good cars.
Maybe it suits my style, maybe I'm more relaxed, more prepared. It's a race that I really enjoy, plus the atmosphere and surroundings of Melbourne."