Ahead of today's second practice session, the air temperature is 23 degrees C, while the track temperature is 43 degrees.

We say practice session but in reality it is a tyre test to enable Pirelli to try its proposed 20205 compounds.

As a reminder, in terms of updates, Red Bull has a new Coke/Engine Cover and Front Corner, both being circuit specific to aid with cooling. Ferrari has new Cooling Louvres. Specific to the requirements of the circuit, these new bodywork exit louvres are extending the top end of the engine cooling capacity, at the expense of car efficiency.

McLaren has a new Coke/Engine Cover, Cooling Louvres and Floor Body, the last of which has been heavily revised, with geometric changes in all areas, resulting in an increase of aerodynamic load across all conditions.

Williams has a new Beam Wing and Coke/Engine Cover, again circuit specific. The engine cover to cover the increased PU cooling requirements that result from the altitude, a larger bodywork exit is available to increase the air flow through the coolers.

RB has new Floor Fences, Floor Edge, Coke/Engine Cover and Cooling Louvres. The revised floor fences improve the quality of the vortex formation on the fences, reducing the aerodynamic losses downstream.

Mercedes, Aston Martin, Alpine, Stake and Haas do not have any upgrades.

There were a number of young drivers on duty this morning, Antonelli at Mercedes, Drugovich at Aston Martin, Bearman at Ferrari, Schwartzman at Stake and O'Ward at McLaren, replacing Hamilton, Alonso, Leclerc, Zhou and Norris respectively.

Russell was quickest earlier, ahead of Sainz, Tsunoda and Verstappen, while the session was red-flagged after Albon and Bearman collided.

Seemingly, Verstappen suffered from a leak in the turbo intake pipe late in the session. In addition an new floor had to be fitted after a piece of metal apparently from a bridge onto the track, causing damage to the underside of the car.

The lights go green, Norris is first out, followed by Alonso, Zhou, Gasly and Ocon.

As more drivers emerge, all are running the prototype tyres.

The teams each have to perform two performance runs and then two long runs. Some teams have two sets of the same compound, while others have two different compounds.

RB has the C5 and C6, as does Williams, while Alpine has two sets of the C4 tyres for its drivers.

Hamilton sets the early pace with a 19.688, until Bottas and then Perez go quicker.

Sainz goes top with an 18.276 as Gasly goes off at Turn 1 and takes a long, long trip over the grass.

"I still hear a weird noise in the engine," reports Verstappen, who is told the team is happy for him to continue.

"This noise is very disturbing, it can't be normal," insists the Dutchman who is told to pit.

"What the hell, the brakes don't work at all," moans the three-time world champion.

Sainz raises the bar with a 17.809.

At Williams, James Vowles admits that it is going to be a "struggle" to get Albon out on track following his crash earlier. Amongst other things the team has had to change his engine and gearbox.

At which point the session is red-flagged after Russell goes off and into the barrier at Turn 9.

Judging by the tyre tracks he lost the car quite early on.

Replay shows he ran over the kerb in Turn 8, bottomed out and became a passenger as the car headed towards the barrier opposite. That's his second crash in a week.

Seen holding his ribs as he got into the medical car, Russell is taken to the medical centre.

The cameras pick up on the significant damage to the right-hand side of the car.

"This red flag is affecting our plans quite a lot, but we know this happens," says Pirelli's Mario Isola. "It's difficult to predict, but I hope we can get some information from this test as it's the last opportunity we have."

Due to the damage to the TecPro barrier it is quite a long stoppage, Race Control finally announcing that the session will resume at 16:36, leaving 54 minutes of running of this ninety minute session.

Alonso is first out, followed by Magnussen, Stroll, Norris and Colapinto.

As Sainz consolidates his top spot with a 17.699, Piastri goes second with a 17.877.

"We've got the same problem, so box," Verstappen is told. Yet to post a time, the Dutchman drives into his garage and climbs from his car.

The sceptic might wonder whether the three-time world champion simply isn't interested in testing tyres for 2025 at this stage in the 2024 title fight.

Leclerc goes fourth with a 17.887.

"My engine is cutting," I don't know if you can see it," reports Zhou.

Ocon reports a burning smell - much like his teammate in the opening session - but is told to keep going.

Norris and Alonso enjoy a brief battle, the pair, like the three other drivers who 'sat out' this morning's session, have access to an extra set of mediums in order that they can carry out some representative running.

With 5 minutes remaining, Norris, Alonso and Zhou fit the mediums.

Norris improves to fifth with a 17.948, while Alonso improves to eleventh.

Hamilton heads out for a single timed lap on the yellow banded rubber, as Leclerc follows suit.

Norris goes quickest in the final sector but remains fifth, while Hamilton goes seventh.

The session ends. Sainz is quickest, ahead of Piastri, Tsunoda, Leclerc, Norris, Magnussen, Hamilton, Bottas, Perez and Lawson.

Alonso is eleventh, ahead of Hulkenberg, Ocon, Stroll, Colapinto, Gasly, Zhou and Russell, with neither Verstappen or Albon setting times.

Check out our Friday gallery from Mexico City here.