Sebastian Vettel will use a new Ferrari chassis for the rest of the US GP weekend after experiencing problems during Friday's practice.
The German, who could see his chances of claiming a fifth world title disappear during Sunday's race, endured a frustrating Practice Two, as a spin into the gravel was followed by a suspected problem with the axle on his SF70-H car.
The Scuderia have now opted to change the chassis to avoid a repeat of the reliability issues during the rest of the weekend and the move has been approved by the FIA so they won't receive a penalty.
Vettel will be hoping the change in chassis has the desired effect, as despite finishing third quickest during second practice, he was a full half a second behind pace setter and world championship leader Lewis Hamilton of Mercedes.
The 30-year-old, who has not won a GP since triumphing in Hungary in July, is confident he can quicikly get up to speed with the changes to his car, with Practice Three and qualifying scheduled to take place at the Circuit of the Americas on Saturday.
"It's important to feel comfortable," Vettel said. "Obviously we're missing some laps but I'm sure with a couple of successive laps tomorrow it should be better."