Both drivers have taken on a new internal combustion engine (ICE) - their fifth of the season - and are set to be hit with a subsequent five-place grid drop for now.

Red Bull and Alfa Romeo may yet decide to add further components into Perez and Zhou’s respective engine pools later in the weekend, which would trigger a bigger penalty. 

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Ferrari's Charles Leclerc is also expected to take on a new power unit in Austin and incur a grid drop, though this is yet to be confirmed. 

With Robert Shwartzman making his FP1 debut in Leclerc’s car, Ferrari decided against introducing new engines on Friday. 

Instead, these changes are expected to be made overnight and confirmed when Leclerc hits the track for final practice on Saturday afternoon.