Christian Horner has revealed how Sebastian Vettel's relationship with Red Bull all started through the young driver writing a letter to the team.
Vettel achieved four World Championships with the Milton Keynes-based squad between 2010 and 2013, but long before then his journey began in a very humble way.
Horner can recall how Vettel – who has announced that he will retire from F1 at the end of the 2022 season – became a part of the Red Bull Junior Team as a teenager.
"What he's achieved is remarkable," Horner told Channel 4.
"I think back to the time that he did with us. He arrived as a 13-year-old. He got introduced to Red Bull by writing a letter asking for sponsorship.
"His first deal was a crash helmet from Red Bull, and then the journey from there through the junior team, into Toro Rosso and then Red Bull Racing and those four World Championships.
"[They are] unforgettable memories, and he was such a big part of our team. It'll be sad to see him hanging his helmet up."
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Horner explains what Red Bull saw in Vettel
With Vettel being brought into Red Bull's main team early in his Formula 1 career, Horner has been reflecting on the qualities that the outfit saw in the German from a young age.
"There's a lot more to Seb than meets the eye," the team boss said.
"When we were looking for a replacement for [David Coulthard], he was the emerging young charger.
"What we saw in him [was] that he's got a great sense of humour. He's a deep, deep thinker, [with a] huge work ethic. He'd be longer in the paddock than any other driver poring over data, and [that] made him so popular within the team.
"But you could see his passion for other things growing as well, and he obviously feels very strongly about all the things that he's representing, which I think is great to see, and he's been a great ambassador."
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