Ferrari Team Principal Fred Vasseur has detailed the "most difficult" moment while trying to sign Lewis Hamilton that ultimately led to one of the most sensational moves in Formula 1 driver market history.
Hamilton will switch to Ferrari next year after exercising an option in his current Mercedes contract, which was set to expire at the end of 2025.
It will be the first time since his F1 career began in 2007 that he will be without a Mercedes engine as he looks to close out his glittering career at the iconic Italian team with an eighth Drivers' Championship.
Vasseur will be reunited with Hamilton after the seven-time champion raced for him at ASM and ART during their days competing in the Formula 3 Euroseries and GP2 (now F2).
When asked about how the talks were started with Hamilton by RacingNews365, Vasseur told media: "We have had a good relationship now for more than 20 years.
"We were always in contact to speak about different things and it basically came [up] naturally.
"I don't know what was easy or what was not, but it came step by step."
Hamilton will go up against Charles Leclerc as his team-mate, a call Vasseur said was no hardship given the Monégasque's existing relationship with the team.
"He's part of the Ferrari family for years now, we know each other very well, I have a good relationship with his management," said Vasseur.
"It was a very direct and straightforward decision, we know also the skills of Charles and so it was an easy one."
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Vassuer: Not the easiest call to Sainz
Hamilton's move means Carlos Sainz will be without a drive at Ferrari, leading to two difficult phone calls that Vasseur faced when luring the Briton away from Mercedes.
"As you can imagine, it was not the easiest call of my life," said Vasseur with regard to the initial chat with Sainz. "The one that was the most difficult was the one with Toto!" he exclaimed, referring to his good friend in Mercedes Team Principal Toto Wolff.
Vasseur has no doubt Sainz will still perform this season in the best interests of the team, despite knowing it is his last year on the grid with the Scuderia.
"I'm fully convinced that he's a very professional driver, he understands that it's a long season in front of us, that it's a huge opportunity," said Vasseur.
"It's also a dream to be in this situation to the team behind him. We had a long discussion, but as you can imagine we will be fully supportive with Carlos. He is fully committed, and we know that we have to do the job together."
Despite Sainz's loyalty to the team, and his expressed desire to remain with the Scuderia, despite a difficult campaign last year in which he was the only non-Red Bull driver to win a grand prix, it was suggested to Vasseur that axing the Spanish driver was "unfair".
Vasseur, though, replied: "Unfair is not the right word because for the team, the opportunity to have Lewis is something that you have to consider.
"He is the biggest personality in the field, the guy with the most experience, so it's a huge opportunity for us.
"It has nothing to do with Carlos. He did a great job last year, and I am sure he will do a great job this year. He's very professional, we have a very good personal relationship.
"But it is like it is and we have to be focused on the future."