Haas has revealed that a plastic sandwich bag lodged in Kevin Magnussen's front wing was the cause of his pace drop off in Formula 1's Singapore Grand Prix.
Magnussen had looked on course for an eighth-place finish at the Marina Bay circuit but it all went wrong around the final safety car period when a clear plastic bag got stuck in the left side of his front wing - badly affecting the car's aerodynamics and effectively dashing his chances of a points-scoring result.
It is thought the bag cost Magnussen around four seconds per lap of pace once it became lodged on his car.
The team had no choice but to pit him to remove it five laps before the end of the race because he was losing too much time and was also destroying his tyres.
"It was after the [final] restart, when he all of a sudden got slower," said Haas team principal Gunther Steiner.
"He drove by a few times and we checked [the wing] because one of the engineers said we can see a loss of front downforce, and we thought the wing was broken.
"But Kevin said he didn't hit anything, and you could not see it when he was driving by as the wing was up.
"That is why we made a pitstop, as he [had] lost so much downforce, so he came in and we put new tyres on and took the bag out.
"The tyres were going, so there was no point to stay out there. At least with a new set of tyres we could put a nice lap in and we see what it is. We got the bag."
Magnussen used his fresh tyres to set the race's fastest lap, but did not get the bonus point for it because he was outside the top 10.
When asked by Autosport if he felt the bag had cost the team points, Steiner said: "It didn't help.
"You start to think that the front wing is broke and you lose downforce, and then the car doesn't work any more.
"Without the bag would we have been able to keep the tyres alive? I don't know."
Magnussen eventually finished 17th thanks to the late pitstop, with his team-mate Romain Grosjean coming home 11th.
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