After Adrian Newey claimed his concerns about the development path of Red Bull’s RB20 went unheeded, Christian Horner says Red Bull’s car troubles were already in play during the Briton’s time as chief technical officer, “certainly during 2023”.

Red Bull announced last May that Newey would leave the team in early 2025 after an extended gardening leave period during which he’d still work on the RB17, Red Bull’s hypercar.

Red Bull issues were ‘certainly during’ Adrian Newey’s time

Additional reporting by Thomas Maher and Sam Cooper

The 66-year-old left the team with one final title, his 26th overall, as Max Verstappen won the F1 2024 Drivers’ Championship in a Newey-spearheaded Formula 1 car.

But stepping back from the team’s Formula 1 operations after the Miami Grand Prix announcement, Newey handed the reins over to technical director Pierre Wache. The Briton’s departure coincided with a dip in Red Bull’s performance as the development of the RB20 went awry.

Balance problems created a “disconnected front and rear”, as Horner put it, making the car difficult to drive and costing the drivers lap time.

It led to a 10-race winless streak for Red Bull, their longest since 2020, and put pressure on Verstappen in the Drivers’ standings while Red Bull were overhauled by McLaren and Ferrari in the teams’ race.

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Newey, who officially joins Aston Martin next month, said he had concerns about the design path but that others in the team weren’t particularly bothered.

He told Germany’s Auto Motor und Sport: “I think, Red Bull, from what I could see… the 2024 car, and through the very last stages of ’23 as well, I would say, started to become more difficult to drive.

“Of course, that suited Max, and he could handle that, if you like – it didn’t suit him, but he could handle it. Checo [Perez] couldn’t. So you also started to see more of a difference in performance between the team-mates, Max and Checo.

“That carried into the first part of ’24 but the car was still quick enough to be able to cope with it.

“It’s something I was starting to become concerned about, but not many other people in the organisation seemed to be very concerned about.

“From what I can see from the outside, but I don’t know, the guys at Red Bull – this is no criticism – but I think they just perhaps, through lack of experience, kept going in that same direction, and the problem came more and more acute to the point that even Max found it difficult to drive.”

Horner was asked about the design guru’s comments and while he wasn’t aware of them, he believes Red Bull’s problems were already around in 2023 when Newey was the man in charge of the design team.

“I haven’t seen those comments, but I think the issues are more deep-rooted than just last year,” he told the media including PlanetF1.com at the F1 75 launch event.

“I think that they’d actually start… when you really dig into the data and some of the characteristics, you start to see them much earlier than that. Certainly during 2023.

“I think that it was a matter of unravelling it to understand what were the contributing factors to having a very peaky performance. That’s where the team have worked very hard tounderstand that and address it.

“The team have worked very hard over the winter to work on some of the vices of RB20. I think we’ve had a good winter. And, you know, the team has been working incredibly hard.

“We’ll get the first sort of indication next week as to, you know, have we managed to address some of the issues. We managed to improve them during the course of certainly the latter third of last year. And we’ll see if we’ve managed to go a step further over these early races.”

Red Bull will run the 2025 RB21 just ahead of pre-season testing getting underway, the team holding a private filming day in Bahrain on February 25 to shake down the new car.

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