Williams team principal James Vowles revealed working with Carlos Sainz has exceeded his expectations.

After negotiations up and down the grid in 2024, Sainz ultimately chose Williams as his destination for the next part of his career, with Vowles adding his team now has “two world class drivers instead of one.”

‘Very rare’ Carlos Sainz abilities revealed by Williams boss

Sainz joined Williams from Ferrari on a multi-year deal at the start of 2025, with the hope of bringing the team forward after several years battling in the lower midfield.

After a tricky start, the 31-year-old grew into the season as he became used to his new machinery, earning two podiums as he and Alex Albon were among the closest teammate battles on the grid for points in 2025.

That helped Williams’ fortunes improve, earning fifth in the Constructors’ standings.

For his contribution, team boss Vowles suggested Sainz’s ability to offer pinpoint accurate feedback is something seldom seen among drivers.

Joking that ‘Sparkles’ the unicorn had been the Spaniard’s big contribution to the team, Vowles went into detail about what the four-time Grand Prix winner has added to Williams.

“It’s been better than I expected,” Vowles told PlanetF1.com and other outlets.

“Because, first of all, some elements to him, I didn’t know until he came here.

“Number one, when you put pressure on him, he gets better. He needs pressure to effectively perform in a better way. I didn’t know that about him, but that’s a great trait to have as a driver.

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“Number two, the level of detailed feedback that I’ve provided before, when he’s able to go to another level of detail, that’s very rare for a driver to have. And again, I didn’t know that before I signed him.

“I just knew he was very good, and his collaboration and his culture, his beliefs, his values, are exactly the same as Alex.

“You can see that happening here. We have two drivers that want to push the team forward, and you’re never sure when you sign someone if that’s really going to be how it is, and the answer is yes.”

Vowles did admit, though, that both he and Sainz thought his best performances would arrive earlier in the season after his move from Ferrari, but given he was moving to a different chassis and power unit, some crossover time was to be expected after four years with the Scuderia.

Despite that, the way he works with Albon gives Williams confidence in its own processes, with both drivers on the same page when it comes to feedback.

“The beginning of the year was more that it took longer than I thought, and that Carlos thought as well, to really get used to how the Williams is,” Vowles explained, “because it’s a very different car to the Ferrari, but the results are here now. The car’s quick, it’s just a different way of extracting it.

“He correlates with Alex really well. They both have exactly the same drive and what they want out of the car, which gives you strength of knowledge.

“I know it sounds odd, but one voice perhaps doesn’t drive you. Two voices saying the same thing absolutely gives you direction on it.

“His way of working, especially with the aerodynamic teams, the vehicle dynamics teams, is very, very good.

“He has an ability to drag you through the data and take you exactly to a point where he’s suffering with a balance issue, which then allows you to dig deep inside it. So it’s that level of detail that he brings with him.”

Additional reporting by Mat Coch and Thomas Maher

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