Jenson Button predicts a long and "exciting" winter of development ahead for McLaren-Honda as it searches for the "big step" it needs to challenge for wins in 2016.
McLaren returns to the Brazilian Grand Prix this weekend, the scene of its last victory in 2012. This year has seen the team struggle with new engine suppliers Honda and the team facing its worst finishing position in the constructors' championship since 1980 if it cannot overtake Sauber before the year's end.
The current engine regulations mean Honda is unable to tackle the bulk of its energy recovery issues until the winter and Button says the lessons of this season will be vital.
Asked what he will take from the 2015 campaign, Button said: "Lots of learning! I know we keep saying it but it is still a very young partnership. We've learned so much this year with the power unit, with the idea of the aerodynamics of the car because it's very different to a normal McLaren. So there's a lot of learning to take from this season. We obviously need to take a big step next year -- we know that -- so it's going to be a long, hard winter, but an exciting one as well."
Button thinks the new partnership has demonstrated its strength through adversity this season.
"We have a lot of strengths and everyone knows McLaren and what they've achieved and it is still the same team. In terms of what we do on a race weekend I think we're doing a very good job, we're getting the best out of what we have and maximising the potential of what we have at the moment. The issue for us is that our project is a lot younger than others so it does take time.
"During a season it's very difficult to make big changes but this winter is a very important one for us to make those changes and come out a lot stronger, because we don't want to be where we are, we want to be fighting near the front. Whether we can win races or not is another question but I think we can at least fight at the front next year."
Button thinks people are surprised by the positive atmosphere at McLaren because the team has struggled so much for performance this year.
"There's a lot of hard work going on and another positive with this team is the confidence; even in difficult times like now there's still a lot of confidence in the team and they're still working flat-out to improve the car and the power unit. There's a good atmosphere, which a lot of people are surprised about but there really is.