Haas driver Kevin Magnussen has revealed that his team don't fully understand why they struggled with their tyres in Mexico.
Magnussen was a furious figure during the race in Central America, describing the tyres as a "discrace".
Haas had a bit of a nightmare at the Autodromo Hermanos Rodriguez, with Magnussen finishing 15th and his team-mate Romain Grosjean a place below him.
Magnussen was asked in Thursday's FIA press conference if his team had figured out what went wrong with their tyres two weeks ago, and the Belgian replied: "Not quite.
"But I think we understand that it's probably to do with tyres as we hadn't changed the car so the only thing that can really be such a factor is tyres.
"I think in Mexico, you have these factors like you have very little downforce because of the altitude and that kind of has a lot of knock-on effects on different things. Cooling as well. You run the car in a different window in Mexico and I think we got the tyre performance a little bit wrong so we suffered a lot in Mexico, and that was a weekend to forget, definitely."
Magnussen did admit, though, that Mexico City's track has been a weak circuit for his team in the three years since its debut there.
"We need to learn from it because last year, and the year before that, the team also had a bad weekend in Mexico. So hopefully next year we can learn a bit more and get there a little bit more prepared to not have such a big 'off weekend'."