Lewis Hamilton's arrival at Maranello meant that Carlos Sainz had to make way for the seven-time champion. This made the Spaniard appear as a "cork" in the bottle as he remained indecisive about his next team. In an attempt to clear his concerns around Mercedes, Sainz had a conversation with Hamilton, which DTS' microphones picked up.
The 2024 silly season started early on February 1, 2024, Hamilton was announced to join Ferrari on a multi-year contract from the 2025 season. With Charles Leclerc being secured for a long-term drive with the Scuderia, Sainz had to find a new home on the 2025 grid.
Nonetheless, the 30-year-old took over five months to decide which team he would join. Carlos Sainz was in talks with a myriad of squads and was speculated to join Mercedes, offering a simple exchange of drivers for Ferrari and Mercedes.
However, the German giant won its last championship in 2021 and had struggled to understand the intricacies of the ground effect regulations. To ensure his future in F1 would remain in winning ways, Sainz talked with Lewis Hamilton about Mercedes' future and said, via Planet F1:
"I haven’t talked to Toto yet. Which makes me feel like if he really had an interest, he would have already called me. You dont think Merc will win again? Do you think they are declining?"
Subsequently, the seven-time champion replied with:
"No, I don’t think so."
Mercedes promoted its prodigy Kimi Antonelli to the F1 realm for the 2025 season, while Carlos Sainz joined Williams on a multi-year contract with the Grove-based squad.
Carlos Sainz asserts that Williams is not too far from the sharp end of the grid

Considering that the Spaniard was one of the seven drivers to have won multiple races, a switch to a backmarker team seemed odd. However, Williams had expressed their desire publicly to sign the four-time race winner.
The project's prospects and common ambitions led Carlos Sainz to join the blue outfit. Since then, he has driven Williams' machinery on three occasions and stated that the team is not far from the front end of the field, as he said, via GPBlog:
"So if you just tell the midfield, last year where it ended, at least in a track like Abu Dhabi, it was not miles away from the top of the field. Where that gap really opens is in the race runs. That's where the downforce and everything tends to make a big difference, and that's where we've or at least me with the team, I'm putting a lot of the focus in trying to improve the race performance in this car."
Sainz will make his debut for the Grove-based team at the Australian Grand Prix on March 16. The English team is understood to have made a step up as it posted the fastest laptime of the pre-season testing in Bahrain.
Though the fuel loads and run plan remain unknown, the FW47 is expected to be one of the contenders in the upper midfield.