A dry and trouble-free day of running for all three drivers across both practice sessions at the Autodromo Hermanos Rodríguez.
Lando got into Fernando's cockpit for FP1 and both he and Stoffel focussed on tyre compound and aero tests with no major issues. Lando finished in 15th with Stoffel less than a tenth behind in 16th.
In the afternoon Fernando got back behind the wheel, and alongside Stoffel continued the tyre evaluations from the first session, before turning their attention to longer runs in the final stages. Stoffel set the 15th fastest time with Fernando in 19th.
Fernando Alonso: "It's always a pleasure to come and race on this unique track, with low air density, fast straights and little grip. We had good feelings today. In FP2 we were testing different things that we carried on from FP1, and obviously the biggest issue was the tyres. There seems to be quite high degradation, so we wanted to check both compounds - also because there might be some rain tomorrow. We have gathered good information.
"This is the kind of circuit where you need to adapt to a lot of things. It's mechanically very demanding because of the engine and brake temperatures, so all in all we had an important day of testing.
"It's difficult to guess where we'll be tomorrow and on Sunday, because the Hypersoft tyre only gives you one lap. Some of the top guys today on that lap maybe had traffic or a lock-up and didn't put the lap together, which I think they will do tomorrow, so the pecking order will be more 'normal'.
"The Stadium is a unique part of the circuit, possibly not made for F1 cars, because it's too slow and maintaining the tyre temperature there is the main thing to get a good Sector. But, you feel the warm atmosphere there, with 80 per cent of the grandstands full on a Friday. It's impressive!"
Stoffel Vandoorne: "It was a reasonable Friday. I think for everyone the talking point was probably the tyres today. It was important for us to be on track and see the long runs, and we split the tyre compounds between us to see the degradation. I think everyone's been struggling with it a lot today.
"It's a very slippery track to start on too and there's a lot of evolution, so we'll see how that goes. Actually, for us I think it would be a good thing if it's like that on Sunday - it would definitely make the race more entertaining.
"It's hard to tell where we are in the competitive order as the field is actually very tight. The Red Bulls are definitely a step ahead but behind them it seems very close, so if we figure a few things out on our side and gain a little bit of performance we might be in for something good. The most important thing is going to be managing the tyres, and that's going to be the biggest chance to score points here."
Lando Norris: "Overall, FP1 was a tricky session. It's my first time here in Mexico City. The session was a combination of a lot of tyre degradation and a dirty track, which made the car really difficult to drive, so it was quite easy to make mistakes.
"I had some lock-ups here and there, but overall we got through the run plan that we needed to do, and I think I gave myself a good feeling of the car and the track. That's the main thing for me, so that when I come back here next year I feel more confident straight away.
"In terms of driving the car, it was very tricky - the lowest downforce I have driven on. It was good to experience something different again, and in terms of my learning it was a productive session."
Gil de Ferran, Sporting Director: "Today was pretty much a normal Friday for us. Lando did his customary good job in FP1. We explored a lot of different options to seek a good balance for the unique requirements of this track, and also did our best to try and understand the behaviour of the tyres.
"The track changed a lot throughout the day and we expect another change tomorrow, with variable weather, which will make for a very complex puzzle heading into Sunday."
Check out our Friday gallery from Mexico City, here.