Carlos Sainz is already thinking beyond the winter rebuild and into the bones of Williams’ 2026 car — and he’s eager to put fingerprints on everything that matters.
After a first season in blue that yielded two podiums and helped haul Williams to fifth in the Constructors’ — their best return in almost a decade — Sainz isn’t basking. He’s plotting. And he’s eyeing the new rulebook as both a grand opportunity and a trapdoor.
What’s got his attention most? The power unit. With Formula 1’s 2026 reset bringing a fresh chassis concept and a radically different engine formula, Sainz believes the hardware behind his right foot could be the defining split in the field.
“The engine is going to be huge,” he said in Abu Dhabi, making no secret of where he sees the early gains. Williams will continue as a Mercedes customer, and that long-standing partnership — plus team boss James Vowles’ deep Silver Arrows pedigree — should ensure the right lines are open when it comes to integration and drivability. In an era where software maps, energy deployment and lift-and-coast windows could make or break Sundays, having two experienced hands like Sainz and Alex Albon feeding into Mercedes High Performance Powertrains matters.
If that’s the macro view, Sainz is just as animated about the micro. For the first time at Williams, he’ll help steer the whole concept from day zero: the setup philosophy, the cockpit feel, the baseline balance the team rolls out of the garage with at round one. That’s where he thinks Williams can quietly bank laptime before the development war even begins.
Drivers love to talk about “tools” and “operating windows,” but with 2026 set to change the load profile, the aero balance and the way the hybrid systems deliver power, the driver-car handshake will be rewritten. Sainz knows this is where details become decisive — pedal maps, diff settings, brake-by-wire sensitivity, how the rear axle behaves when the battery is peaking or empty. It’s not glamorous, but it’s the kind of stuff that gives you a car you can fight with at the limit.
There’s confidence at Grove after 2025. Williams took its chances, executed cleanly and, crucially, put Sainz in position to convert them. Two trips to the rostrum were the headline moments, but there was a more important throughline: the team’s Saturdays improved, the race pace became predictable, and strategy calls stopped feeling like coin flips. Fifth in the championship wasn’t a fluke; it was the sign of an operation that’s learned how to maximize what it has.
And yet, Sainz isn’t getting drunk on the progress. He doesn’t see the 2026 shake-up as a guaranteed springboard; he sees it as a hard reset. If the rules had stayed stable, he admits, you could reasonably bank on Williams continuing to chip away at the front — they were often a couple of tenths off pole and race-winning pace on their better weekends in 2025, and the team has a clear map of its weaknesses. With a stable platform, incremental gains stack up.
But a reset is a reset. Someone will go bold and nail it. Someone will miss, chase their tail until midsummer, and wonder where the year went. There’ll be loopholes. There always are. That’s why Sainz’s message is measured: stay focused, keep the expectations tidy, concentrate on controllables. Nail the car’s foundation. Work the integration. Let development breathe once the racing starts.
The upside for Williams? This isn’t a team stumbling into new regs. The Mercedes supply gives them a known quantity on the PU side, Vowles has lived through dominant regulation cycles before, and in Sainz and Albon they’ve got a pair who can articulate exactly what the car’s doing and why. That’s gold dust when so much of 2026 will be about joining the dots between chassis airflow and hybrid energy flow.
Sainz sounds ready to get his hands dirty, and that’s half the battle. Influence the concept. Shape the cockpit feel. Keep the car friendly from the first laps on Friday. Then, when the lights go out, use the software and energy systems to sharpen the weapon you’ve built. It’s not romantic, but it’s how surprise packages are made in a reset year.
Williams climbed back into the fight in 2025. The next step is tougher and far less predictable. Sainz knows it — and he wants a say in every decision that might tip the balance.
