"One of the most special moments for me today was when I arrived at the circuit and I saw the Ferrari with my number 55 on it! I was eager to jump in the car and that first installation lap was exciting."
Watching from the sidelines were the Spaniard's father, Carlos Sainz Sr, Leclerc and head of the Ferrari Driver Academy, Marco Matassa, who previously worked with Sainz during his time at Toro Rosso.
Sainz drove over 100 laps on his first day, putting to use the knowledge gained in meetings with the team to get used to the in-car procedures, many of which the team claim will be relevant to this year's SF21.
"I am very pleased with how the day unfolded," he added.
"We were able to get through an extensive programme and I was able to familiarise myself with the whole setup: the engineers and mechanics, the steering wheel, the procedures which are obviously a bit different to those on the car I drove last season.
"It was very nice to have my father there at such an important moment in my career."
He concluded: "I am very happy and could not have wished for a better start."
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