Lewis Hamilton says he hasn't been driving 100 per cent on the limit since he secured a fourth world championship earlier in the season.
The Briton grabbed a fourth title at the Mexican Grand Prix with a ninth-place finish, which was all he needed to beat Sebastian Vettel, but in the final two races he's missed out on pole position and the wins, finishing fourth in Brazil and second in Abu Dhabi.
Hamilton, who has never won a race after a title win in the same season, admitted it wasn't easy to remain on the same level when the target has been achieved.
"I have tried my hardest to stay on it but I wouldn't say it was 100 per cent of what it was while in the season," aaid the Briton. "You want to enjoy it. I do still try and turn up and do the job but it's not so easy.
"It's clear that something happens once you've won the championship. All I can say is that in the week after I won the championship, I partied a lot. That's what you do. I didn't do that before the other races."
Hamilton has no concerns that could impact his 2018 season: "The energy has not been the same, even if I have approached the races the same. But I'm not worried about that. Next year it will go back to what it was in the second half of the season."
