(Motorsport-Total.com) – The 2026 Barcelona-Catalunya Grand Prix ended with a second place for George Russell – and yet with an open need for explanation in the Mercedes camp. Although the Brit secured pole position on Saturday and was also on the podium on Sunday, the race revealed increasing problems with balance and tire degradation from the middle of the race onwards.
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Especially in the last stint, Russell lost significant pace compared to teammate Lewis Hamilton, who won the race for Ferrari. Mercedes has now confirmed that an error during the last pit stop played a crucial role.
Already in the second race segment, Russell had complained about increasing understeer. This development led to the tires being more stressed and the car becoming increasingly difficult to control as the race progressed.
These balance problems simultaneously opened the door for several developments in the field: Lewis Hamilton was able to make up time with his three-stop strategy, while Andrea Kimi Antonelli in the Mercedes steadily closed in and at times even appeared to be a real threat for a podium position. The Mercedes strategy was to specifically correct the balance during the final pit stop.
Planned front wing adjustment goes wrong
During the last stop, the team was supposed to adjust the front wing using the designated adjustment device. The goal was to reduce the previously occurring understeer, improve the aero balance, and stabilize tire wear. But it was precisely at this point that a technical problem occurred.
As Mercedes later explained, the necessary adjustment tool did not work as intended. “In our last pit stop, we incorrectly adjusted the front wing due to a problem with the adjustment device,” explains Bradley Lord, Deputy Team Principal of Mercedes.
“That meant he was running with a very strong oversteering balance, which definitely affected his pace in the final phase.”
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From understeer to oversteer: complete balance flip
The consequence of the error was serious: instead of a planned more neutral setup, Russell suddenly drove with a significantly oversteering car. This meant an unstable rear, less confidence in fast corners, and significantly increased tire wear on the rear axle – precisely where the load is particularly high in Barcelona anyway.
Particularly critical: the change from understeer to oversteer did not happen gradually, but almost abruptly after the last stop. For a driver, this means a complete readjustment of driving style in the middle of the final race segment – under conditions where the tires are already heavily stressed.
A look at the data confirms the effects of the error. In the last stint, Russell lost an average of one second per lap to Lewis Hamilton. The time loss was not immediately noticeable in the first few laps, but intensified especially towards the end of the stint, as the tires on the rear axle increasingly degraded due to the oversteering balance. Mercedes emphasizes, however, that not everything can be attributed to the error.
No victory guaranteed even without errors
Even in the first laps of the last stint, when the tires were still fresh, Russell could not quite keep up with Hamilton’s pace. Although traffic and finding the balance again played a role, the gap was already visible there. This suggests that Ferrari had the stronger package overall this weekend – regardless of the Mercedes problems.
Hamilton’s victory was therefore not solely explainable by strategy or errors in the Mercedes camp, but also by pure pace. Barcelona is traditionally considered a track with high tire stress, especially on the rear axle. Already on Friday, Pirelli had reacted to increased temperatures and critical wear values and adjusted the air pressure to improve the contact patch.
In this already sensitive environment, an incorrectly tuned aero balance can have particularly major effects. A car that oversteers or understeers too much inevitably leads to increased slip – and thus to faster tire degradation.
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