Zak Brown believes Red Bull have yet to face the “full consequences” of losing the likes of Adrian Newey, and 2026 could be even more dire with their new Red Bull PowerTrains engine.

Red Bull announced the departures of several key personnel last season, headed by long-time design guru Newey who had played an instrumental role in the team’s success since arriving from McLaren in 2006.

McLaren chief: That still poses a big question mark for Red Bull

Designing championship-winning cars for Sebastian Vettel and Max Verstappen, Red Bull announced in May that Newey would be taking a period of gardening leave before ending his association with the team.

Stepping back from Red Bull’s Formula 1 operation to focus on the RB17 Hypercar, Newey’s departure from the frontlines coincided with Red Bull’s first fumble in the ground-effect aerodynamic era as the team made a misstep with the floor they introduced at the Hungarian Grand Prix.

Red Bull did return to the top step of the podium but not before Max Verstappen recorded his longest winless streak, 10 races without a P1, since 2020. Red Bull and the Dutchman bounced back to win the Drivers’ Championship, the fourth in a row.

Red Bull, however, missed out on the double as they fell to third in the Constructors’ standings with Sergio Perez unable to match his team-mate’s results in the RB20.

Newey’s exit was followed months later by news that stalwart Jonathan Wheatley, Red Bull’s sporting director, would be saying goodbye to the team at the end of 2024 before joining Sauber as the new team principal this summer. Red Bull’s head of race strategy Will Courtenay is also off to a new team, joining McLaren in 2026.

McLaren CEO Brown believes those big-name departures could yet trip up Red Bull in 2025.

“Red Bull has lost the necessary important people and I think we haven’t seen the full consequences of that yet,” he told De Telegraaf. “It is a good team, but you also have to look at the culture and the atmosphere.”

However, it’s in 2026 when the McLaren chief reckons Red Bull’s biggest challenge awaits as the team introduces their own engine, designed in partnership with Ford.

Red Bull Powertrains was established in 2021 and as of next year will power Red Bull and Racing Bulls in Formula 1.

“For them, 2026 will be an even bigger challenge,” Brown continued. “That’s when they come with their own engine for the first time, and I don’t remember a team with its own engine being immediately competitive in the first year.

“That still poses a big question mark.”

As for McLaren, the Woking team is hard at work designing their 2025 challenger, the MCL39, with Brown revealing the team is set to take some risks with the new car as they chase their first Drivers’ title since 2008.

“We will compete with four top teams,” Brown insisted. “I can divulge that we are going to develop the car considerably. I am impressed by how brave the team is in terms of plans for next year.

“We are really going to make a lot of changes. In Formula 1, you also have to take risks if you want to be the best. I don’t think you have a choice.”

McLaren won the F1 2024 development war, the team nailing every one of their upgrades while rivals fumbled. That not only saw the team take the teams’ trophy ahead of Ferrari, but Lando Norris bagged a career-best P2 in the Drivers’ standings with Oscar Piastri fourth.

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