Red Bull have one major concern after looking at the data from the Japanese Grand Prix

Red Bull got their 2025 season up and running at the Japanese Grand Prix as Max Verstappen claimed his first win of the year.

The Dutchman converted pole position to victory at Suzuka as he fended off pressure from the McLarens throughout the race. Verstappen finished just 1.4 seconds ahead of Lando Norris as he benefitted from having clean air in front of him.

The win at the Japanese Grand Prix puts the reigning four-time champion a point behind his rival going into Bahrain this weekend. Red Bull will be eager to carry the momentum after what has been a difficult start to the season.

Verstappen and Liam Lawson struggled to get to grips with the RB21 in the opening two races. While the former could extract the maximum in Melbourne and Shanghai, the latter was dramatically off the pace.

The New Zealander was demoted to Racing Bulls after failing to reach Q2 in the opening two rounds and score points. Yuki Tsunoda has replaced him as Red Bull seek better results from the second car – but even their star driver has been struggling.

Verstappen is ‘extremely annoyed’ over the RB21’s performance compared to McLaren and has stressed that every upgrade brought to the car must work. While Japan was a step in the right direction with victory, there is still a major concern for Red Bull.

Red Bull had a different setup in ‘virtually every parameter’ from the simulator data for the Japanese Grand Prix

The Milton Keynes-based outfit went into Suzuka with high hopes. Verstappen had won the last three events in a row, while new signing Tsunoda had impressed in the simulator ahead of his debut.

It seemed as though Red Bull found the right operating window for the RB21 to grab pole position and the win in Japan. Verstappen went just 12 thousandths of a second quicker than Norris, with Oscar Piastri in third just 44 thousandths behind the Dutchman.

While the team did find performance, it came from changing the setup from the simulator, which had given the team a completely different idea ahead of the weekend.

Speaking via Auto Motor und Sport, chief advisor Helmut Marko slammed the simulator’s readings, telling Verstrappen before the race to rely on his experience rather than the data in Milton Keynes: “Whenever the simulator promises us great lap times, things go backwards on the racetrack,” he said.

“That was the case two years ago in Monte Carlo and again this time. I told Max he should rely on his experience rather than what the simulator says.”

The AMuS report goes on to say that Red Bull ‘had to set up its cars differently in virtually every parameter than the simulation data suggested’ to win in Japan. This is a huge concern for the team as it continues to leave them in the dark about where the car actually is in terms of performance.

While the different setup worked at Suzuka, as Melbourne and Shanghai proved, it will not work at other circuits. McLaren have a clear pace advantage and Red Bull will need to iron out their issues if they want to fight across the season.

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Red Bull’s difficulties with the simulator highlight how incredible Max Verstappen’s Suzuka performance was

Red Bull do not know how to fix the RB21 and risk falling further behind their rivals if they cannot find a solution. But if Suzuka proved one thing, it is that Verstappen cannot be counted out of the championship race.

Despite having an inferior car, the Dutchman has produced solid drives thus far in 2025. The Japanese GP was another example of the 27-year-old’s incredible talent.

Peter Windsor lauded Verstappen’s ‘astounding’ lap in qualifying as he found performance from the RB21 seemingly out of nowhere. Red Bull have struggled to match McLaren’s pace in 2025, but it is clear the Dutchman can still challenge the Woking squad.

Christian Horner says Red Bull are focused on Verstappen and his title chances. This should come as no surprise, but it is a warning for McLaren that the four-time champion can still cause a headache even if they clearly have the quickest car.