“It became very clear in Bahrain that we had a problem, which was really strange because in winter testing and in the first race the car was really good,” said Magnussen to MotorsportWeek.
“Even in Bahrain in qualifying, we qualified… I can’t remember, sixth of something, up there. Then in the race it just completely fell apart.
“So from there on it was a little bit of panic in the team.
“We couldn’t really focus on… kind of find the real root of the problem. We were looking a lot at tyres and blaming the problem on tyres issues whereas in fact it was a little more simple.
“We just had aero issues, unstable aero and the whole platform just not being strong enough and consistent, stable enough.
“It’s a very frustrating problem, because we have [been] able to qualify well but in the race we just have not had any strength.
“That’s very frustrating as a driver, where you start in a position and then you’re just fighting to try to hang on to your position rather than attacking the guy in front.”
Haas will be working hard to ensure that they are competitive next season and will hope that they can climb their way back up the grid.