Isack Hadjar will start Sunday's Miami Grand Prix from the back of the grid after his Red Bull was disqualified from qualifying, the governing FIA said.
The French driver had qualified ninth in Saturday's session and the stewards' decision promoted Alpine's Pierre Gasly to his compatriot's slot with Audi's Nico Hulkenberg moving up to 10th.
Hadjar's car failed a post-qualifying measurement inspection with a small section of the floorboard protruding millimetres beyond the limit in what Red Bull admitted was an error on their part.
"We made a mistake and we respect the decision of the stewards," said team boss Laurent Mekies.
"No performance advantage was intended nor gained from this error."
The race start has been brought forward by three hours after weather forecasts predicted thunderstorms and lightning in the area of the Hard Rock Stadium. Mercedes' Kimi Antonelli starts on pole for the third race in a row.