Charles Leclerc believes Ferrari have some work to do in order to optimise their setup due to the challenges presented by the Circuit of the Americas.
The Monegasque driver finished FP2 in P7, just 0.011s back on Aston Martin's Lance Stroll. Leclerc says the bumpy track surface, along with high track temperatures, made it hard for him to find a suitable balance.
Nevertheless, he is keen to figure things out before qualifying on Saturday.
"In terms of our sessions, we ran through the planned programme, testing a bit of everything," Leclerc said after FP2. "What was challenging were the bumps on the track which made it very tricky to drive.
"With temperatures running quite high, tyre management was a key factor. Tyres overheated, especially in the third sector. You have to find a perfect balance between pushing in the first sector while losing time in the last one, or saving the tyres in the first part to be quicker at the end of your lap.
"We will do some more work in FP3 to understand how to optimise this ahead of qualifying."
Teammate Carlos Sainz, who finished FP2 in ninth, believes tyre degradation could make things tricky on Sunday.
"We tried different setups today and improved a bit from FP1 to FP2," said Sainz. "Overall, I'm happy with our Friday and the pace is promising, taking into account I got traffic in Sector 3 of my fast lap and couldn't close an otherwise good looking lap.
"Track temperature was very high and that obviously had an effect on the long runs, where degradation appeared quickly on the Softs. That could make things tricky come Sunday, so we'll keep an eye on it."
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