Ferrari team principal Marco Mattiacci thought an initial approach to take the job last week was an April Fool's joke.
The Italian revealed at the Chinese Grand Prix that he was first offered the role last Friday, but believed it to be a joke.
"I live in New York and I received a call at 5.58 on Friday morning," said Mattiacci.
"The chairman, [Luca] di Montezemolo, was on the phone and he told me, 'this is my idea'.
"I told him that April Fool's [day] had been about 15 days earlier. But then, after the second or third minute of discussions, I understood that it was serious.
"And I understood that as there was already a ticket ready to go from New York to Milan after three hours.
"I arrived Saturday morning in Maranello at the Fiorano track."
Mattiacci was brought up to speed with the demands of the job by his predecessor Stefano Domenicali, having spent two days with him before travelling to Shanghai.
"Stefano is a great person. He is a friend of mine," he said. "On Saturday we spent a few hours [with each other], and Monday we spent the entire day together.
"Stefano is a person who I have the utmost respect as a human being and secondly as a professional, so it was natural to discuss the roles."
And it was the speed by which events happened last week that explained why Mattiacci took the unusual approach of wearing sunglasses in the pits during the gloomy Friday sessions.
His fashion statement became a major discussion point on social media channels.
"If you do in less than four days almost 40 hours of flights, and you don't sleep in the last four days, then probably you need sunglasses," he said.