George Russell has set his sights on becoming World Champion while at Mercedes, though he's under no illusion about the challenge that awaits him next season.
With Valtteri Bottas leaving the Silver Arrows for Alfa Romeo, the Briton will drive alongside Lewis Hamilton after spending the last three years at Williams.
Russell is aware that a challenge awaits him at Mercedes, however that hasn't stopped him from aiming for the ultimate prize next season.
"Signing the Mercedes contract was one of the greatest moments in my life, but it is only the first step," Russell told Bild. "The really hard work has yet to come.
"To drive for a team like Mercedes and alongside Lewis Hamilton – if I thought it was easy, I would be foolish.
"I am happy, but I also know that things are only really getting started now. It's going to be the greatest challenge I've ever faced.
"I know what it took to get here. Getting into Formula 1 is not the end. My goal is to become World Champion."
Russell will only become a full-time Mercedes driver next season, but he's been part of their junior driver programme since 2017. The youngster explained how he introduced himself to the team.
"I emailed Toto [Wolff] in December 2014, quite late in the evening, that I had sent him my resume and that I would like to meet him," Russell added.
"The worst that could have happened is that he doesn't write back. But only 15 minutes later he replied: 'Let's make an appointment.'"