Ahead of today's opening practice session, the air temperature is 25 degrees C, while the track temperature is 35 degrees.

In terms of updates, Ferrari has a new floor, Alfa Romeo a new beam wing (without flap), Aston Martin new bodywork (cooling louvres), Haas a new floor and AlphaTauri mirror winglets and front wing.

And, err, that's it... nothing declared by Red Bull, Mercedes, Alpine, McLaren or Williams.

The lights go green and Alonso leads the way, followed by Bottas, Magnussen, Stroll and Hulkenberg. As more rivers head out it's a mixture of hards and mediums.

In no time all, all bar Albon are on track, the Williams driver duly emerges.

Complaining of a vibration on his steering wheel, Russell is told that it is not possible in this session. He insists that he would rather lose half-an-hour of running than continue as the vibration gets worse.

He duly pits.

Of the first wave Verstappen goes quickest (34.054), ahead of Hamilton, Perez, Magnussen ad Hulkenberg.

As Albon complains of "sup low grip", Sargeant reveals that he cannot move his head.

Early offs for both Perez and Hamilton.

Hulkenberg goes second with a 34.401 as De Vries brings out the double yellows when he spins at Turn 11.

The stewards have noted the Dutchman for "dangerous driving".

Perez is told that he's losing out to his teammate mainly in Turn 1.

No sooner has Sainz gone quickest (22.832), than Hamilton responds with a 32.967.

However, a 32.465 sees Verstappen retake the top spot.

Alonso's first flying lap sees the Spaniard go fourth with a 33.583.

Verstappen describes the grip as "hit and miss", "one millimetre offline and you're..." he warns.

Sainz goes third, ahead of Perez, Alonso, Leclerc and Ocon.

After 16 minutes, Bottas, Zhou and Russell have yet to post times.

Quickest in all three sectors, Verstappen extends his advantage to 1.141s with a 31.826.

Verstappen is the latest to run wide, the Dane going off at Turn 17.

"A lot of sliding everywhere," complains Gasly.

A brilliant save by Albon in Turn 16 as the rear of the Williams attempts to break away from him. The Thai driver doing well to keep it out of the barriers.

Alonso improves to third with a 32.542 as Leclerc posts a 32.528 to go second.

Twenty-five minutes in and the Haas pair are the first to switch to the softs, as Ocon goes sixth and Piastri seventh.

On the red-banded rubber, Hulkenberg goes purple in the first two sectors, finally crossing the line at 31.392 to go top.

As Sargeant and Stroll fit the red-banded rubber, Magnussen goes third with a 31.853.

Albon goes fourth on the softs, as Alonso aborts his first flying lap after making a mistake.

On the red-banded rubber, Verstappen stops the clock at 31.054 while teammate Perez goes third (31.581).

Oh dear Hulkenberg has hit the wall at the exit of Turn 3. Replay shows his losing the rear as he exited the corner. "I lost it," he reports.

The session is red-flagged.

As Verstappen said earlier, once you veer even slightly offline you run out of grip.

With the session red-flagged and around 22 minutes remaining, it's: Verstappen, Hulkenberg, Perez, Magnussen, Albon, Leclerc, Alonso, Hamilton, Ocon and Piastri.

The session resumes with 18 minutes remaining, Albon leading Perez and Verstappen back on to the track.

While the rest are on softs, Hamilton and Russell are on mediums.

Verstappen ups the ante with a 30.549, while Bottas goes tenth (32.865).

Alonso goes fourth (31.633) and Ocon fifth (31.846).

A 31.072 sees Leclerc go second, while Piastri goes sixth, ahead of Ocon, Magnussen and Albon.

Zhou improves to twelfth (32.178), as Russell goes sixteenth with a 32.910.

Sainz goes second with a 30.993 as Albon runs wide in Turn 17, a corner which has caught out a few drivers today. Moments later Gasly is off at Turn 7, having previously improved to sixth with a 31.414.

"Lost the rear in high speed," he reports, "I just completely lost it, very strange."

Leclerc retakes second with a 30.802, just 0.253s down on Verstappen.

Quickest in the final sector, Hamilton goes quickest overall with a 30.337. Moments later, teammate Russell stops the clock at 30.125.

The session ends but the 'moments' continue, Russell tripping up overran Aston Martin and Sargeant running wide.

"What the **** is he doing," says Tsunoda off a wayward Alpine, "f****** idiot!"

Russell is quickest, ahead of Hamilton, Leclerc, Verstappen, Sainz, Gasly, Alonso, Stroll, Hulkenberg and Ocon.

Perez is eleventh, ahead of Piastri, Magnussen, Bottas, Albon, Norris, Zhou, Tsunoda, Sargeant and de Vries.

Check out our Friday gallery from Miami here.