The head of Red Bull's driver development program has said it was simply a case of unfortunate timing for Sainz with Red Bull due to Max Verstappen also appearing on the scene in 2015.
“Why didn’t we take Sainz? Because we have Max,” Marko told La Gazzetta dello Sport. “Our policy is to have the best driver with a good team-mate.
"At the start, he was simply unlucky that Max Verstappen came in at the same time. But I am convinced that Carlos will benefit Ferrari now.
“If Carlos wants to become a race winner, then he will have to learn how to overcome difficulties, such as the struggle with Charles Leclerc."
After completing almost three seasons at Toro Rosso, Sainz was forced to forge his own path out of the team, initially on loan to Renault for the final four grands prix of 2017 before signing a deal that saw him remain with the French manufacturer through 2018.
The 25-year-old Spaniard then joined Mclaren in 2019, and after a strong campaign - which included a trip to the podium in Brazil - Ferrari came knocking with an offer he could not refuse.
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