Max Verstappen's tricky United States Grand Prix weekend took another blow on Sunday morning when he was hit with a grid penalty because of a gearbox change.
Verstappen was due to start the Austin race 15th after failing to take part in the second part of qualifying because he damaged his Red Bull's lower right-rear wishbone after running wide on the kerbs at the exit of Turn 15 during Q1.
That hit, and Verstappen subsequently limping back to the pits, could have caused minor damage to the gearbox.
While grid penalties for the two Toro Rosso drivers should have elevated Verstappen to 13th, a precautionary gearbox change eliminates any risk at relatively low cost.
A new gearbox means a five-place penalty and Verstappen will start 18th.
The Toro Rossos of Pierre Gasly and Brendon Hartley are locked into the back row of the grid because they have taken multiple new Honda engine components.