Carlos Sainz calls for major design changes at Williams to improve long-corner performance. An unexpected incident during the Belgian Grand Prix qualifying has sparked controversy .

Carlos Sainz has publicly urged Williams Racing to change the design philosophy of its 2026 Formula 1 car to better suit his driving needs and to address key weaknesses that have limited the team’s competitiveness on certain circuits.

Speaking after the Hungarian Grand Prix, Sainz criticised the FW-series car’s poor performance in medium- to high-speed corners, where maintaining downforce throughout the entry and mid-corner phase is essential.

“It is crucial to change our design approach so that the next car can perform at its best across a variety of circuits,” Carlos Sainz told AS. “We have an aerodynamic deficit in long corners, where it is vital to keep the downforce from the corner entry to the apex. This weakness has been a constant for a long time. Because of this, our car performs better in tight corners and on long straights. On tracks like Barcelona, Hungary or Qatar, we really struggle.”

Despite the team’s current struggles, Sainz has been working closely with engineers to provide detailed feedback, using his experience from competing with front-running teams in the past. “I went from a team that was fighting for pole positions to one where I am starting from 13th place. I can give very strong feedback on what this car is lacking on circuits like this,” the Spaniard said.

At present, Carlos Sainz sits 16th in the drivers’ championship, while his teammate Alexander Albon holds a much stronger eighth place. Adapting to a completely different team environment and getting used to the Mercedes power unit has been a challenge for the former Ferrari driver. In the most recent race in Hungary, Carlos Sainz finished 14th, with his last points finish coming in Canada, where he took 10th place.

Williams has already shifted much of its resources towards preparing the 2026 challenger, with the incoming technical regulations making next year’s design process more important than ever. The British team is not alone in this forward-looking approach—Aston Martin is also heavily focused on the future, with former Red Bull technical mastermind Adrian Newey already at work on a car designed to fight at the very front of the grid.