The cars of both Nico Hulkenberg and Kevin Magnussen failed post-race scrutineering and were referred to the stewards for an issue with the DRS system.
Following a hearing, it was found that both cars were not in compliance, leaving stewards no option but to exclude the pair from the session.
“The Technical Delegate discovered on examination that the uppermost rear wing element adjustable positions exceeded the maximum allowed under Article 3.10.10.h of the Technical Regulations of 85mm,” the stewards summary noted.
“The team explained that this was the consequence of an inadvertent error on their part in setting the wing flap gap.
“The wing used was a new design that was used for the first time in Monaco.
“The old design was set to be compliant with the regulations with the largest gap measured from the centre of the wing. Under the new design, the largest gap was at the extremities of the wing but the team had not trained its mechanics to set the gap per the new design, resulting in the non-compliance.
“The duty to comply strictly with the Technical Regulations rests at all times with the Competitor.
“The team suggested that there was no performance advantage gained by the non-compliance. Article 1.3.3 of the International Sporting Code makes it clear that this is irrelevant.
“The team was candid in admitting its error.
“The wing was otherwise compliant with the Technical Regulations and the FIA technical team confirmed that they were satisfied with the team’s explanation for the error.”
The penalties will see Hulkenberg drop from 12th on the grid, and Magnussen 15th, to the last row.
Hulkenberg will start ahead as he was the higher placed of the two Haas drivers in Free Practice 3.
The flipside is it will result in a one-place gain for Daniel Ricciardo, who’d otherwise qualified 13th.