Despite repeatedly denying he lost focus in the final races of the 2015 Formula 1 season, Lewis Hamilton has now admitted his 'frame of mind' did indeed shift after he clinched his world title last year.

The Mercedes driver wrapped up his third career world title with three races of the 2015 season remaining amidst a highly-charged tussle with team-mate Nico Rosberg, only to end the year being comfortably defeated by the German in Mexico, Brazil and Abu Dhabi.

Though Hamilton was quizzed several times as to whether he had lost motivation now the title was his, the Briton repeatedly denied this was the case, even going as far to say changes to the car's suspension in the final third of the year was losing him time.

However, as Hamilton returned to action for the first pre-season test of 2016, he concedes that he lost focus following the title win. Despite this, he says it doesn't mean he didn't enjoy that period, despite losing out to Rosberg in the races.

"I haven't really taken a huge amount from those last few races," he said. "My frame of mind shifted after I won the championship last year; the intensity of the championship was over, and I enjoyed it more than I have ever enjoyed the end of a season in my whole career both inside the car and out.

"I still arrived and did the job in terms of scoring the points for the team, but, yeah let's see where it goes from the beginning of this year."

With a third title under his belt, Hamilton is certain he won't trouble mustering motivation for a fourth and is hopeful there is still more to come from him.

"I think there's more to come. I'll show that through the rest of the season, but we'll see how the first races go

"Mentally I feel very strong; I feel absolutely determined to get back in and win - it's just in my DNA, the spirit to win, so it's not like I have to go and reinvent myself or find extra motivation from thin air - it's just there, thankfully.

"I'm sure the competition is going be stronger than ever this year and I want to make sure that I'm stronger than ever so that I can face whatever's thrown at me."