Carlos Sainz has climbed into Williams’ 2026 car for the first time in earnest, completing his seat fit in the FW48 at Grove as the team works through a delayed start to its new-era campaign.
Williams shared images of Sainz in the factory on Thursday, captioned: “Another piece of the puzzle complete.” It’s a small milestone in isolation, but one that lands with a bit more weight given Williams is the only team sitting out this week’s collective shakedown in Barcelona.
James Vowles has been candid about the decision. Speaking to select media on Wednesday, the Williams team principal described missing Barcelona as “incredibly painful” and admitted it “clearly wasn’t our plan”. The team has blamed “delays in the FW48 programme”, but Vowles framed the root cause as a consequence of intent rather than error — Williams pushing hard under the sweeping 2026 regulations.
That matters because the easy reading from the outside is always “they’re late”, full stop. Inside F1, it’s rarely that simple. The sport’s winter isn’t won by the first car to turn a wheel at a damp shakedown. It’s won by the team that shows up to the meaningful tests with the right parts, enough spares, and a development path it can actually execute.
Vowles’ argument is essentially that Williams could have gone to Barcelona — but at a cost he wasn’t willing to pay. He said the team would’ve risked being short on spares and key components when it counts, across the two Bahrain tests next month, the season build-up and the opening Australian Grand Prix on March 8. In his words, there were “zero points” on offer for running in Barcelona, and the internal evaluation leaned towards virtual work and preserving the broader programme.
“In terms of Barcelona, we could have made Barcelona testing — simple as that,” Vowles said. “We could have made it, but in doing so I would have to turn upside down the impact on spares, components and updates across Bahrain, Melbourne and beyond.
“The evaluation of it was that for running in a cold, damp Barcelona, against doing a VTT [virtual test track] test, against the spare situation… we made the decision. I stand by it that the right thing to do is to make sure we’re turning up in Bahrain correctly prepared and prepared in Melbourne as well.”
It’s hard not to hear the subtext there. Williams has lived this pain before. In 2024, the team arrived in Australia without enough hardware to run two cars properly, fielding only a single entry. Vowles didn’t need to spell out the reputational hit — everyone in the paddock remembers it. And there’s an extra twist of irony: that 2024 Australian Grand Prix was won by Sainz, then still at Ferrari.
Now Sainz is the one being asked to buy into a longer-term plan at Williams — and, to his credit, he did exactly that through much of 2025. After the noise of his high-profile move from Ferrari, his first season in blue started quietly and finished strongly. Two podiums, third in Azerbaijan and Qatar, plus the same result in the United States sprint, was a tidy return for a driver who didn’t come to Grove to tread water.
The seat-fit imagery, then, is less about a photo op and more about Williams moving into the phase where excuses stop being useful. Once the driver’s position is locked in and cockpit ergonomics are signed off, the car becomes a real thing rather than a project plan. For Sainz, it’s also the beginning of the feedback loop Williams will need if it’s going to make a step under regulations that demand teams relearn their assumptions.
The 2026 ruleset is not a tweak; it’s a reset — with 50 per cent electrification, fully sustainable fuels and active aerodynamics all arriving at once. Williams is a long-term Mercedes customer, and like others on the grid it’s had this season ringed on the calendar for some time. Vowles insisted he’s “confident” missing Barcelona was the right call, because the priority is arriving at Bahrain with enough parts, enough mileage potential, and enough headroom to respond when something inevitably breaks.
That’s the gamble. Skip early running and you remove one kind of risk — the risk of burning through finite components in poor conditions — but you invite another: the risk that the first proper track day exposes issues you’d rather have found quietly in Spain. Williams is betting that its factory work, simulation correlation and sheer preparation will cover the lost time.
Sainz’s seat fit doesn’t answer whether that bet will pay off. But it does underline that Williams is now in the business end of winter: the point where every day becomes expensive, and every “we’ll be fine” has to survive contact with reality.
The next time we see the FW48 move in anger should be Bahrain. That’s when this story stops being about why Williams wasn’t in Barcelona — and starts being about whether it was right not to be.
