Christian Horner says Lewis Hamilton's move to Ferrari has shocked the entire F1 world, including his current team Mercedes.
Red Bull and Mercedes have been battling it out for the sport's biggest honor for the past decade, but that could change over the next few seasons with more teams lining up for the championship.
One of those companies was Ferrari, which pulled off the scoop of the century by luring seven-time world champion Hamilton from Brackley to Maranello.
Christian Horner gives his opinion on Lewis Hamilton's move to Ferrari
Mr Horner, speaking at the launch of the RB20 in Milton Keynes, said the move had even driven out companies like Mercedes.
“First of all, I think it surprised everyone, including the existing team.” [Mercedes]about Lewis' transfer to Ferrari,'' he told media such as PlanetF1.com.
“He's obviously seen something there that he believes is more beneficial to him than staying there. I think the partnership between Lewis and Ferrari is a really exciting thing for F1.”
As for when Mr. Horner's Mercedes representative, Toto Wolff, learned about it, the Austrian said he was informed over coffee the day before the announcement.
“When we re-signed Lewis, we opted for a shorter term,” Wolff said after the announcement.
“So this incident is not surprising. [but] Maybe timing. So what happened was we met for coffee at my house in Oxford and when he came back to the factory he told me he had decided to race for Ferrari in 2025.
“That's basically it. We talked for a good hour, and…this is where we belong.”
Recommended by PlanetF1.com
Lewis Hamilton's shock transfer forces Mercedes to make an incredibly daunting decision
Revealed: The astonishing 36-hour timeline behind Lewis Hamilton's shock Ferrari move
Horner's future is not very secure, as he made the comments while under investigation for alleged inappropriate conduct. The 50-year-old denies all the claims, but admitted he was “distracted” ahead of the new season.
“There were inevitably some distractions, but the team is very united,” he said. “Everyone is focused on the season ahead. It's very much business as usual. The support has been great.”
“Obviously my focus is very much on the season ahead. It has been business as usual.
“There is an investigation that I am fully cooperating with and that is going on behind the scenes as we prepare for the upcoming season.”
Read next: Christian Horner admits pre-season 'distraction', Red Bull investigation ongoing