Alpine's Pierre Gasly has been disqualified from Formula 1's Azerbaijan Grand Prix qualifying for falling foul of the FIA's fuel flow regulations.
After qualifying 13th in Baku, Gasly's car failed scrutineering as FIA sensors revealed the Frenchman's engine "exceeded the instantaneous fuel mass flow" during Q2.
Gasly was thrown out of the results soon after, which is the latest setback for Alpine after a troubled weekend.
Team-mate Esteban Ocon parked after just three laps in FP1 with MGU-H issues, leading to an engine change.
Ocon broke down again at the start of FP3 with a fuel pump failure and would end up qualifying last after tagging the wall in Q1.
Gasly is now set to join him and Sauber's Zhou Guanyu, who is taking an engine penalty, at the back of the grid, unless Alpine decides to use the opportunity to make further changes and start from the pitlane instead.
"The Technical Delegate reported that Car 10 exceeded the permitted 100Kg/h fuel mass flow on the final timed lap of Q2," the stewards' verdict read.
"The team representatives explained that they had an unexpected short duration technical fault that raised the fuel mass flow greater than expected in a transient fashion. The cause was agreed by the FIA technical staff.
"That the fuel mass flow was greater than the limit at that moment was not disputed by the competitor.
"The competitor demonstrated to the Stewards that the technical fault resulted in a slower lap time and that no performance advantage was obtained at that moment.
"Thus, they argue, this should be taken into mitigation. They also noted that the great rarity of breaches of this article demonstrates that this is not part of their strategy, and that the scale of the transient simply exceeded the margin they maintain to prevent a beach.
"The usual penalty for a breach of the technical regulations is disqualification and the Stewards note that Article 1.3.3 of the International Sporting Code states 'If an Automobile is found not to comply with the applicable technical regulations, it shall be no defence to claim that no performance advantage was obtained.' In addition to the Code this has long been the position of the International Court of Appeal.
"Thus, the Stewards apply the usual penalty and disqualify the car and driver from the classification of qualifying."
After what he had called the most difficult Friday of the year, Gasly said he had actually defied expectations by surviving Q1 and qualifying 13th in the first place.
"It was amazing. I thought it would be 17th and 18th, ended up in 13th so I can't really ask for much more," Gasly said before learning of his legality issue.
"It was an extremely tough weekend since FP1, just couldn't get the car working anywhere. We made some changes, everything we've done went in the right direction so I think that's positive. I managed to [pull off] all my laps in Q1 and Q2.
"Obviously, I wish I could be further up the grid, but with the car we had and compared to the others, I think we did the absolute best, so happy with that. We know on pure pace we should not be there."
Speaking about his woes, Ocon said his lack of track time meant it was hard to judge where the limit of the car was, which led to him tagging the wall exiting Turn 4 and puncturing a tyre.
"Missing two sessions on a street circuit, it's a weekend where you can't really build the confidence, you can't really set the car up and we've missed that," he lamented.
"You are into full risk mode, and you can't really dictate if that's the limit or not. It wasn't the first time I clipped the wall there, but that time luck didn't seem to be on our side, because the tyre came off as well."
