Mercedes has initiated a comprehensive investigation into the ‘very strange’ car behaviour experienced by both George Russell and Kimi Antonelli during the recent São Paulo Grand Prix. The team secured the 2026 Formula 1 Constructors’ Championship at Interlagos, but the race was marred by unexpected handling problems for both drivers.
Both Russell and Antonelli reported significant instability from their W17 chassis, particularly after transitioning from intermediate tyres to slicks. This marked the first Grand Prix of the 2026 season where Mercedes failed to secure a podium finish.
Kimi Antonelli, the reigning 2026 Drivers’ World Champion, started the race from second position on the grid. He initially led the Grand Prix but subsequently experienced an uncharacteristic spin on track.
Antonelli reported unusual handling characteristics over team radio, suggesting a potential suspension issue. He lost control at Turn 1, surrendering the lead to Lando Norris, and ultimately finished the race in fifth place.
George Russell also encountered significant difficulties, including a bizarre spin in the pit lane immediately after his switch to slick tyres. The incident forced him to manoeuvre his Mercedes back into position, briefly dropping him to tenth before he recovered to fourth.
Mercedes Team Principal Toto Wolff acknowledged that the team might have made an error with its tyre pressures or car setup. Wolff noted that neither Russell nor Antonelli are prone to such unforced errors.
Both reported a very, very strange behaviour of the car, like something’s broken on the suspension or too much pressure in the tyres.
Wolff also highlighted an unusual discrepancy in tyre wear, with the rear tyres showing complete degradation while the front tyres appeared almost new. This suggests an imbalance in load distribution across the car.
The Autódromo José Carlos Pace at Interlagos is a 4.309-kilometre circuit known for its 15 corners, significant elevation changes, and unpredictable weather. It demands a precise balance of mechanical grip and aerodynamic stability.
Pirelli supplied softer compounds for the 2026 São Paulo Grand Prix, nominating the C3 as Hard, C4 as Medium, and C5 as Soft. Resurfacing work between Turns 3 and 5 and Turns 8 and 9 may have influenced grip levels.
The team’s technical department at Brackley is now conducting a thorough investigation. The focus includes suspension kinematics and potential shifts in aerodynamic balance under varying fuel loads and tyre compounds.
Mercedes’ W17 chassis has previously exhibited balance issues, particularly understeer, following an aerodynamic upgrade introduced in Malaysia. This update reportedly shifted the car’s balance forward.
Earlier in the 2026 season, the W17 was also subject to FIA scrutiny regarding its active aero system. Mercedes front-loaded its development programme for the W17, resulting in fewer major upgrades later in the year.
Despite the race difficulties, both Mercedes drivers demonstrated competitive pace at times. Antonelli recorded the fastest lap of the race, and both he and Russell achieved strong average stint times.
Wolff noted that Max Verstappen also reported some car instability during the race. However, the consistent and severe nature of the issues for both Mercedes drivers was distinct.
Kimi Antonelli secured his ninth victory of the 2026 season at the United States Grand Prix, demonstrating strong strategic execution. Russell has experienced a challenging season with fluctuating performance despite three race wins.
