Lewis Hamilton believes his 2019 Formula 1 world title triumph has been his hardest at Mercedes taking on challenges both on and off track.

The British driver wrapped up his sixth F1 world championship with two races to spare thanks to second place at the United States Grand Prix which sees him with an unassailable 67-point advantage over teammate Valtteri Bottas.

Despite seeing Mercedes dominate to take both F1 world titles for a sixth consecutive season, an unmatched feat in the sport’s history, Hamilton reflects on 2019 having overcome a number of tough moments.

Off the track Mercedes had to overcome the death of Niki Lauda during the unrelenting 21-race season along with a resurgence from both Ferrari and Red Bull.

As a result, Hamilton sees this season as “the harest year for us as a team” but takes great pride in helping secure another dominant campaign in F1 having already secured 10 wins along with six additional rostrum finishes with two races to go.

“No way has it been the easiest. It’s been the hardest year for us as a team,” Hamilton said. “We lost Niki this year.

“A crucial member and a real pivotal member of our team and the emotional rollercoaster that we’ve been on with losing him, and a race where I didn’t have Bono [Pete Bonnington, Hamilton’s race engineer] here, outside of the car, just trying to remain focused throughout the year.

“That is the toughest, and only really other athletes who are at the top of their game can really, probably related to it, probably because it’s just: arrive: week-in, week-out, can’t drop the ball and being about to bounce back from the tough, lower days.

“This car has not been easy for us. We started the season honestly going off to Melbourne thinking that we were going to be behind. Mid-point of the season we were behind, and it’s been a real challenge, this second half of the season. It’s been the toughest second half of the season that I think we’ve had as a team, fighting against Ferrari and Red Bull, which is great, we welcome that.”

While Hamilton accepts each F1 season provides different challenges he’s been eager to be honest to both his Mercedes team and the watching world – something he feels has helped him as a result.

“Every year you go through a different rollercoaster ride of emotions to get to where you’re going,” he said. “I wrote something in my post, that each and every single one of us is struggling with something in life. Whatever it may be, small or big.

“I tried to show people that, from the outside, things always look great but it’s not always the case. And I am also struggling with lots of different things and battling certain demons and trying to make sure that I’m constantly growing as a person.”