Two drivers have been disqualified from Singapore Grand Prix qualifying over a rear wing infringement.
Mercedes' George Russell qualified on pole for the race on Sunday, ahead of Red Bull's Max Verstappen and McLaren's Oscar Piastri.
Lewis Hamilton was sixth in his Ferrari, one place behind title contender Lando Norris.
Further down the grid, however, Williams are set to have both cars starting from the back of the grid.
Advert
Both Alex Albon and Carlos Sainz's cars were placed under investigation by the FIA over a rear wing infringement that was picked up during post-qualifying scrutineering.
The issue relates to the DRS element on both cars' wings.
An FIA statement, from F1 technical delegate Jo Bauer, reads: "The uppermost rear wing element adjustable positions were checked on car numbers 23 [Albon] and 55 [Sainz].
"Both cars exceeded the maximum limit of 85mm on both sides of the rear wing outer area.
Advert
"As this is not in compliance with TR Article 3.10.10 g, I am referring this matter to the stewards for their confirmation."
The investigation resulted in a disqualification for both cars. They will be allowed to compete in the race and are expected to start from the pit lane.
“During post-qualifying scrutineering, the rear wing of the car was found to be non-compliant with the technical regulations,” the stewards noted. “The uppermost rear wing element adjustable positions were checked. The DRS in the state of deployment exceeded the maximum limit of 85mm on both sides of the rear wing outer area.
Advert
“At the hearing, the competitor admitted that, although their own measurement prior to the qualifying had shown the component to be within tolerance, the measurement subsequently conducted by the appointed FIA officials revealed a larger gap than permitted and therefore the rear wing did not conform with the required dimension.
“The competitor did not contest the measurement procedure, the methodology, or the accuracy of the measuring equipment used by FIA. The Competitor fully accepted the results of the FIA measurement and acknowledged that the rear wing fitted to the car did not comply with the requirements of the technical regulations.
"Accordingly, the standard penalty applicable to technical infringements is imposed.”
Williams had qualified in 12th and 13th places, with Albon ahead of Sainz.
Advert
Team principal James Vowles was spotted in conversation with Williams mechanics in the garage after qualifying, with Sky Sports F1 reporter Ted Kravitz noting: "They're both going to get disqualified.
"We believe the DRS has been opening too much, past the 85mm allowed. We've seen that in the past, but certainly not this year.
"Clearly, it's a mistake. You don't put the car into qualifying or into the race knowing its illegal, because there's no point - it's illegal, you get found out and you get disqualified.
"So that's what James Vowles is trying to understand with his engineers and Pat Fry, who is the technical director, how this was allowed to happen.
Advert
"The fact that it's on both cars would indicate that it's either an assembly or manufacturing problem. It isn't the same as the assembly problem that Haas had [Esteban Ocon was disqualified for a rear wing infringement in Azerbaijan]."
Ryan Smart