Ferrari boss Fred Vasseur has said he and Lewis Hamilton "stupidly" underestimated the scale of the challenge he faced when he joined.
The hype around Hamilton's blockbuster move to Ferrari has soured this year, with the seven-time world champion yet to score a podium for the team.
During a difficult Hungarian Grand Prix, a downbeat Hamilton suggested Ferrari "probably need to change driver."
He also added "there's a lot going on in the background ... That's not great."
Team boss Vasseur, who was instrumental in signing him from Mercedes, has defended his driver's form.
Vasseur pointed to the scale of the change for Hamilton.
"Lewis and I, we collectively, probably underestimated the change of environment, and the fact that he spent, for me, 20 years in the same team," Vasseur told The Race.
"McLaren was Mercedes, and then he moved to Mercedes: an English team [a German company which operates out of England], same engine guys, that same culture and so on.
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"So he spent 2006 to 2024, 18 years, in this environment, and then he arrived at Ferrari. And we were stupidly expecting that he will have everything under control."
Teammate Charles Leclerc has been on the podium five times this season.
Hamilton signed for a reported £60 million ($81m)-a-year contract taking him through to the end of 2026.
The Englishman, statistically the greatest driver in Formula 1 history, said from the beginning he was looking at next season, when a complete change of F1 cars comes into force thanks to a new set of rules, for his championship challenge.
