Carlos Sainz is not running a reconstructed 2024 chassis, Williams reportedly confirming they “modified” last year’s as part of the FW47’s evolution.

Despite speculation during the build-up to the F1 2025 that Sainz would be the Williams driver to beat, it’s Alex Albon who is leading the head-to-head battles.

Theory about Carlos Sainz’s ‘strange’ performance quashed

He’s opened his campaign with an impressive P5 at the Australian Grand Prix, a race where Sainz joined the list of those crashing out, while a week later in China, Albon was seventh.

Sainz did manage to break his duck when he was elevated to 10th place after three post-race disqualifications.

Sainz admits he’s baffled by what he called the “strangest” performance swing that he has ever experienced.

F1 2025 head-to-head stats

👉 F1 2025: Head-to-head qualifying statistics between team-mates

👉 F1 2025: Head-to-head race statistics between team-mates

“It is one of the strangest swings of performance that I’ve had in my career, going from naturally and super-quick in Bahrain and Abu Dhabi, even at the beginning of Australia, and then suddenly the pace just seemed to fall away from me,” said the Spaniard.

“We did a lot of setup changes that on my side of the garage, followed really what Alex did, [both cars] were pretty similar.

“On his side, it seemed to respond well to a front graining, and he was a lot stronger. On my side, it didn’t seem to help much, and I stayed struggling with the graining.

“A bit puzzled, to be honest. Not happy, because ever since I jumped in this car, I’ve been very quick in testing, but I don’t know where all that pace has gone. At least we have now a good ten days to analyse what went wrong and put together a plan to come back stronger in Japan.”

One theory about the discrepancy between the team-mates was raised by Spanish journalist Carlos Miquel.

He claimed that Sainz is using one of the reconstructed 2024 chassis that Williams crashed last year and that the team were planning on giving him a new one. As for Albon, Miquel alleged, he was using the chassis Williams ran during pre-season testing.

But this is not the case according to F1 journalist Chris Medland.

Medland took to X, saying there “have been some reports Williams is using an old chassis due to budget constraints, and that it could be hurting Sainz.

“Like many teams Williams modified its 2024 chassis for this year, and both drivers have the same.

“The team says: “The monocoque for 2025 is modified from the FW46, but it is the same one. The FW47 is an evolution as we’ve previously explained, aligned with our 2026 goals.”

“Williams has three chassis, so Sainz isn’t stuck with just one if needed.”

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