Carlos Sainz and Charles Leclerc both believe the altitude of the Mexican Grand Prix circuit was a factor in Ferrari's drubbing, in which they finished fifth and sixth.
On an off-weekend for the team, Sainz was able to finish the race ahead of Leclerc, but the lead Ferrari was 58.123s behind race-winner Max Verstappen, with Leclerc the last car on the lead lap.
It is Ferrari's worst two-car finish of the season, eclipsing their fourth and sixth in Hungary, as a strong points haul for Mercedes reduced the Scuderia' advantage to 40 points in the race for second place in the Constructors' Championship.
However, post-race, both Sainz and Leclerc felt the unique atmospheric conditions found in Mexico - a venue 2,240 metres above sea-level - was a key reason behind their anonymous performance.
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"We knew going into the weekend, with this car, with this altitude, we knew we were going to lose quite a bit of performance," Sainz explained to media.
"We were one minute away [from Verstappen], but I haven't done a race in a month [after retirements in Japan and the United States], so it was nice to actually do it and have a good race with the pace management."
As for Leclerc, who lost P2 in the Drivers' Championship after Sergio Perez finished third to leapfrog him by five points, he felt Ferrari needed to work on optimising the car in difficult conditions.
"Today, I felt like an explanation was that it was a bit of a one-off here to the different conditions and I hope we can come back to our usual performance in Brazil.
"I feel like we've maximised absolutely everything today and, even though we've done that, we are still one minute away from Max, which is a huge difference.
"So, we need to look into making our bad days better, because whenever we have a bad day, especially on a Sunday, it is a really bad day."
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