Red Bull adviser Helmut Marko believes there is an “obvious connection” that McLaren’s car has become tricky to drive since Rob Marshall joined the team at the start of last year.

Marshall became the first big name to leave Red Bull almost two years ago, announcing his decision to join McLaren in May 2023 after 17 years with Red Bull.

Rob Marshall: Red Bull’s loss, McLaren’s gain?

Although Marshall did not officially link up with McLaren until January 2024, the signing of the Red Bull man coincided with a stunning transformation at the Woking-based team, who emerged as Max Verstappen’s most consistent threat in the second half of 2023.

McLaren went on to clinch their first Constructors’ Championship in 26 years in 2024, with the team starting the F1 2025 campaign with two consecutive wins.

Lando Norris came through a dramatic race to convert pole position into victory in Australia, where Marshall joined the British driver on the podium during the post-race celebrations.

Seven days later, Norris’s team-mate Oscar Piastri led a one-two finish for McLaren at the recent Chinese Grand Prix.

Lando Norris vs Oscar Piastri: McLaren head-to-head scores for F1 2025

👉 F1 2025: Head-to-head qualifying statistics between team-mates

👉 F1 2025: Head-to-head race statistics between team-mates

McLaren’s strong start to the season has seen them establish an early 21-point lead in the Drivers’ Championship with Red Bull currently third, 42 points adrift entering this weekend’s Japanese Grand Prix.

Despite McLaren’s commanding position, both Norris and Piastri have remarked that the new MCL39 car has proven difficult to drive at times.

The fast-but-flawed McLaren has drawn comparisons to the recent Red Bulls driven by Verstappen, who has consistently complained about the handling characteristics of his car since last year.

Marko believes it is no coincidence that McLaren’s resurgence began not long after the signing of Marshall two years ago, with his influence “noticeable” in the current car.

Asked if there is a connection that the McLaren drivers are now complaining about the MCL39’s handling, Marko told Motorsport.com: “I think there’s an obvious connection.

“McLaren’s upward trajectory began immediately after that switch — that was the Austrian Grand Prix in 2023.

“It’s clear that some knowhow was transferred.

“Rob Marshall is a very experienced, capable designer and his influence has become noticeable at McLaren.”

Marko’s comments come after Red Bull held a meeting at their Milton Keynes factory last Thursday to discuss how to proceed, with Verstappen’s “wishes and criticisms” of the RB21 high on the agenda.

In a fresh update, Marko has revealed that Red Bull upgrades alone will not fix the team’s current woes with the team aiming to produce a car “more stable” on a wide range of circuits, temperatures and tyre compounds going forward.

He added: “There was a meeting with the lead engineers and Max, where all these issues were openly laid out, along with the solutions we have planned.

“Updates, of course, can work — or they might not. That happens at Mercedes, it happens at Ferrari.

“We’re chasing something much more stable — a car that works on all tracks, at all temperatures, and with all tyre compounds.

“That’s the direction we’re headed in and I’m confident we’ll get there.”

Marshall has since been followed put the Red Bull exit door by the likes of Adrian Newey and Jonathan Wheatley, both key figures behind Red Bull’s success in F1 who have taken up new roles with Aston Martin and Audi F1 respectively.

Newey officially started work as managing technical partner at Aston Martin at the beginning of last month, with Wheatley taking up his new position as Audi F1 team principal today (April 1).

McLaren also announced the signing of Red Bull’s long-serving strategy chief Will Courtenay as the team’s new sporting director last September.

However, Courtenay is not expected to start work with his new team until next year as he fulfils the remainder of his Red Bull contract.

In an interview over the winter, Marshall explained his decision to leave Red Bull for McLaren in 2023 and expressed his relied that he left the Milton Keynes outfit “the right way.”

He said: “From a personal point of view, [McLaren] asked me at the right time.

“I was at a point where I thought: ‘If I don’t move to another team now, I’m probably here forever.’

“I was happy to be there forever. I really enjoyed my time at Red Bull, it was a great place to work. But then you get to the stage where you’re going stale, you’re in denial.

”I think I was finding stuff a bit too easy, a bit too comfortable. You knew everybody, you had to get everything done. It was all a bit slick.

“And I’m thinking, well, five, six, seven years, that’d be happier, then I retire. And then the phone rings saying: ‘Do you want to leave?’

“And you’re about to say: ‘No’. And for some reason, you just can’t. Because at that point, you kind of go: ‘I’ve been kidding myself, I think it’s probably time to go.’

“And at that point, you’re going. If there’s any doubt, you’re going.

“I don’t think you can turn back. If you’ve thought about it long and hard. If you think long and hard about leaving, then you’re gone.

”Now I’m absolutely glad I went and I’m really happy that I left Red Bull the right way.

“You’d like to think no one wants to be indispensable but they’ve clearly been able to manage without me, which is great for them.

”You don’t want to leave anywhere in the lurch.

“I thought I had a really good career there, really enjoyed it and I’m now really, really enjoying at McLaren.

“I think I’m enjoying it as much here now in my first year as I did in the first first few years at Red Bull, which were the fun part.”

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