Sebastian Vettel has been given a three place grid penalty for failing to slow sufficiently for red flags during FP1 on Friday morning.
The German slowed down after being the red flags, but it has been deemed by the stewards that he failed to slow sufficiently.
“Vettel did, in fact, fail to stay above the minimum time set by the FIA ECU in marshalling sectors 6 and 7,” the stewards statement said.
“As the regulation states, Art. 31.6 was added this year to ensure that drivers reduce speed significantly during a red flag.
“Breach of this regulation is seen to be an extremely serious matter.
“To be consistent with previous decisions on similar incidents this year, the Stewards assessed the penalty specified above.”
Vettel can now only start as high as P4 on the grid in Austin on Sunday, knowing that if Lewis Hamilton scores eight more points than he does, the title battle is over.