Carlos Sainz's father has opened up on how the Ferrari star has struggled during a "stressful and hard" year because of Lewis Hamilton's switch to join the Italian giants.

The Spaniard, 30, discovered in February that he had lost his seat with the Scuderia next year as Hamilton, 39, sealed a shock move from Mercedes to replace him.

Seven-time world champion Hamilton will partner Charles Leclerc for the Prancing Horse in 2025, as they look to end their long wait for an F1 title after last clinching the Constructors' Championship back in 2008.

Sainz, meanwhile, pondered his future for several months and was heavily linked with Mercedes and Red Bull, before opting to join Williams on a multi-year deal in August.

Some eight months after the news broke of his impending exit, his father and rally driver Carlos Sainz Snr admitted his son has suffered from the stress of deciding his next move.

"I am a rally and rally raid man and I am not an F1 man," Sainz Snr told Mundo Deportivo. "I collaborate and help my son [Carlos] as much as I can, like any father.

"But yes, it has been a very stressful year in the sense that there have been big doubts, the surprise at the beginning of the year [the announcement that Hamilton would replace Sainz at Ferrari] has been stressful and hard, especially for my son, who is the protagonist."

The past 12 months has been arguably the most successful period of Sainz's F1 career to date, with race victories in Singapore and Australia landing a crucial blow to Red Bull's dominance.

His dad, now 62, is often seen watching his son from the Ferrari garage along with his nephew, Carlos Onoro, who acts as Sainz Jnr's manager.

But while he has witnessed some glorious moments throughout the three-time race winner's career, he still finds it a frightening experience - and even prefers to jump in a rally car than put himself through the ordeal.

"Watching him [is more scary], without a doubt. When I'm driving I don't suffer at all! I have fun," he said. "When you don't have control of the situation and you're just watching from the outside, you suffer more."

Responding to a question about whether he would like to race alongside his son in the Dakar Rally in the future, he explained why such a scenario would be "impossible."

"Firstly, because he would like to be an F1 driver and I would like [him] to be a driver too," he added. "And also as he doesn't know how to drive and I don't know how to drive, it's an impossible task.

"When he decides to do the Dakar [Rally], I don't know how I'll be."