The Spaniard is now searching for his next destination in F1, but his fine form in the opening eight races in 2024, including a stunning win in Australia - have ensured he will have no shortage of offers to consider.
Despite being linked with a host of teams, including Audi and Mercedes, the former McLaren star has kept his cards close to his chest, admitting that he was reviewing all options ahead of last weekend's Monaco Grand Prix.
However, Channel 4 presenter Steve Jones believes the 29-year-old has delivered a strong hint that he knows where his future lies following an interview with the broadcaster in the principality.
Sainz said: "My priority is to want to remain in F1, but also to allow me to find a medium to long-term project where I feel valued, where I feel I'm being listened [to], where I feel like I can commit to a medium or longer term that is going to be useful for my career."
In response, Jones claimed Sainz's words indicated he is set to sign a contract with Williams.
Speaking live on the broadcast, he said: "Very graceful. Very classy. I expected nothing less.
"Just after that interview, the rumours started to swirl that Sainz might be joining Williams.
"It's really interesting to hear him talk about a long-term project with a team. In short, he's going to Williams. It's locked in."
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17 - 19 May
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24 - 26 May
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7 - 9 Jun
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21 - 23 Jun
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28 - 30 Jun
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20 - 22 Sep
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25 - 27 Oct
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1 - 3 Nov
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29 Nov - 1 Dec
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6 - 8 Dec
Gulf Air Grand Prix of Bahrain 2024
Gulf Air Grand Prix of Bahrain 2024 
Saudi Arabian Grand Prix 2024 
Grand Prix of Australia 2024 
MSC Cruises Grand Prix of Japan 2024 
Grand Prix of China 2024 
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