Max Verstappen is set to take grid penalties in the United States Grand Prix as the Dutchman makes what Red Bull hopes will be his final power unit change before the end of the season.
Verstappen is expected to take a new internal combustion engine and at least one other new element on Saturday, meaning he will earn a minimum of 15 places in penalties.
The team opted to make the change in Austin because it's a track where Verstappen has a good chance of recovering well from a poor grid position, because it's relatively easy to pass.
"At least you can overtake so it's not such a problem," Red Bull motorsport boss Helmut Marko told Motorsport.com.
"And it's could be wet. I don't know exactly what will be changed and what won't be. Wait until Saturday."
Toro Rosso's Brendon Hartley also has grid penalties for his first Grand Prix start this weekend.