Williams' Lance Stroll and Haas driver Kevin Magnussen have been handed three-place grid penalties for the United States Grand Prix.
Both drivers had been referred to the race stewards for separate incidents that took place during the first round of qualifying at the Circuit of the Americas on Saturday.
Magnussen was judged to have held up Sergio Perez through turns 13 and 14. The Dane quickly admitted that he had inadvertently impeded the Force India due to a misunderstanding.
"I was told that he was on an out-lap so I didn't let him through. I can understand if he's pretty angry with that," he told reporters afterwards.
"I can only say it was a mistake. I'm sorry about that. I definitely impeded his lap so that gives you a penalty."
The race stewards did indeed decide that Magnussen had been in breach of Article 31.6 of the FIA Formula One Sporting Regulations.
"The driver of car 20 admitted he had impeded car 11," said the penalty notification from the stewards. "The team admitted it had inadvertently incorrectly advised the driver that [Perez] was on an out lap.
"The driver and team apologised to the driver of car 11 for the error."
Magnussen was eliminated at the end of Q1. Perez survived and made it all the way through to the final round. However, the incident still had lasting consequences for him.
"I had to use an extra set of tyres, which meant I went into Q3 with a single [unused] set," he explained. "That hurt me a lot.
"Obviously he didn’t do it on purpose," he continued. "But they – him or Haas – are quite often getting it wrong. I think it’s something they have to improve at."
Despite qualifying last and then being served a three-place grid drop, Magnussen will actually start from 18th place because of penalties to other drivers.
He will also receive a penalty point on his superlicence. It takes him to a total of eight points over the last 12 months.
By coincidence, Magnussen's team mate Romain Grosjean was the victim of the other case of blocking in Q1.
He has been closing on Stroll at high speed through the final corners. The Williams attempted to get out of the way but ran wide instead. That put Stroll into Grosjean's path, forcing the Haas onto the grass to avoid a collision.
"Stroll was on a slow lap, Grosjean on a fast lap. Stroll was changing settings under direction of his engineer and got a very late call about Grosjean overtaking," read the official adjudication.
"Stroll immediately moved right and off the track, but Grosjean was already outside track limits and made the decision to overtake on the right, as Stroll moved right.
"It was obvious Stroll was not able to see Grosjean approaching in his mirrors, and he stated he could not move to the left as Kvyat was passing him on that side.
"The stewards believe Stroll did what he could in the circumstances," continued the stewards. "But nevertheless this was potentially a very dangerous situation as the speed differential between the two cars was in excess of 100 km/h at the apex of Turn 19.
"The stewards believe the team should have given Stroll more advance warning that Grosjean was approaching rapidly."
Like Magnussen, Stroll was handed a three-place grid penalty and a penalty point added to his superlicence. The Canadian, who had qualified in 17th place, will now start from 16th on Sunday after other penalties have been applied.
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