Ferrari boss Fred Vasseur said the relentless focus of Carlos Sainz and Charles Leclerc on each other was unlike anything he had seen before.

Sainz made the move from McLaren to Ferrari in 2021, but four seasons and four grand prix wins later, Sainz’s Ferrari tenure has come to an end, with seven-time World Champion Lewis Hamilton chosen as Charles Leclerc’s new team-mate from F1 2025.

Ferrari believe Carlos Sainz v Charles Leclerc added performance

Additional reporting by Thomas Maher

Hamilton’s arrival means Sainz is heading for Williams, and as Ferrari team principal Fred Vasseur looked back on the Leclerc and Sainz partnership, he confessed that their intra-team battle was at a level he has not seen before.

Not that this was to Ferrari’s detriment.

“I have never in all my time of racing seen two team-mates so intensely preoccupied with what the other one is doing,” Vasseur told Motor Sport Magazine.

“They were incredible in how hard they were pushing each other – out of the car too, in how much work they were putting in. I really believe that competitive fight between them has brought us performance.”

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And Leclerc – who backs Sainz to deliver for Williams – believes his battle with the Spaniard as Ferrari team-mates improved him as a driver.

Sainz joins a Williams team looking to work its way back up to the F1 summit under the leadership of James Vowles.

Speaking alongside Sainz and Lando Norris – Sainz’s McLaren team-mate – following the Abu Dhabi season finale, Leclerc said: “I think Lando and myself are probably the two best persons to speak about it, because we’ve been sharing the same team with Carlos for many years.

“I can tell you, Carlos is so incredibly talented. He’s helped me to improve in so many areas, his work ethic, his talent, and just everything he brings.

“The discipline he has, he’s been just such an incredible team-mate. And I think if today, I will repeat myself, but if today we have done such a step forward in a year and in these four years, it’s a big thanks to Carlos. He’s just been extremely quick.

“In Formula 1, some things you don’t really have explanations for. There’s also luck that is involved to be at the right place at the right time and Carlos definitely deserves to be in a top team.

“But I’m sure that it’s just a matter of time before he comes back and joins us to fight for wins. He will give so much to Williams, the way he’s so sensitive to every small change and every small feeling there is in the car. I’m pretty sure that already tomorrow [in testing] they will have a lot of valuable feedback that will help them for next year.

“I’ll definitely miss the fights. We’ve had our moments on track, but that’s only because we were fighting so close together and because he’s been pushing me all the way. And it’s been an absolute pleasure. And of course, in some moments, in the actual moment, in the present moment, there’s frustration.

“But I’m sure that, and actually already now, I’m looking back at those moments, with a lot of positive memories. And I wouldn’t be the driver I am today without him as my team-mate in the last four years.

“So yeah, it’s been a really big pleasure and four years that I will be looking back in the most positive way. And I wish him the best. But as I said, I have no doubts that he will be back at the top of the grid, whether it’s with Williams by his input or with someone else. But he deserves that. I think everybody knows that. And it’s just a matter of time before he comes back.”

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