Ahead of today's sole practice session, the air temperature is 17 degrees C, while the track temperature is 19 degrees.

Charles Leclerc set the pace in yesterday's only meaningful session, out-pacing his teammate by just over half-a-second. While the Bulls looked competitive - as did Fernando Alonso, Valtteri Bottas and Nico Hulkenberg, who used the old-spec Haas - McLaren and Mercedes were both off the pace.

Following yesterday's drain cover drama, Carlos Sainz has a 10-place grid penalty even though he was the innocent victim.

Red Bull and Mercedes both broken the curfew, but in both cases since this was the first of the two allowed exceptions no further action will be taken.

The lights go green and a minute or so later Piastri leads the way, on hards. He is subsequently followed by his teammate (mediums), Russell (mediums), Zhou (soft) and Bottas (soft).

According to Pirelli, "looking at the split of laps completed between the soft, medium and hard, it seems the last of these is being saved by several teams specifically for Saturday night, with the medium also being very much in the running. Having said that, the soft cannot be ruled out completely, precisely because of track evolution."

Coming here, the Italian manufacturer had two bugbears in mind: warm-up and graining. "As regards the first of those, today we didn't notice anything dramatic or unprecedented compared to what we have seen before in this discipline. As for the second, it was clearly significant, but still in line with what we have experienced at other tracks. Furthermore, we saw today how the graining tended to progressively reduce as the cars did more and more laps, a sign that the situation could change, possibly quite significantly, by Saturday night, opening up opportunities that maybe today seemed unlikely."

Russell posts the first time of the day, a 43.603 but this is soon beaten by Zhou and then Bottas (39.875).

As more drivers head out all three compounds are in use.

Leclerc goes quickest with a 38.953 ahead of his Ferrari teammate who posts a 39.367, both on the yellow-banded rubber.

Despite being first out, neither of the McLaren drivers has posted a time, both opting to scrub two sets of tyres in preparation for tomorrow.

Bottas retakes the top spot with a 38.351 as Hamilton (medium) goes fourth (39.743).

Russell reports "oscillation" on the straights. "We're happy," he is told, "keep doing what you're doing."

Leclerc improves with a 36.508 and Sainz a 37.081.

Magnussen goes third (37.597), as Piastri goes fifth, Stroll ninth and Alonso thirteenth.

A 35.939 sees Sainz go top, the Spaniard quickest in all three sectors.

Magnussen goes off at Turn 5 briefly bringing out the yellows. A few moments earlier the Dane had tangled with Leclerc. "Looks like he's taking the p***," said his engineer. "yes, completely," replied the Haas driver.

With 41:00 remaining Perez and Tsunoda head out, leaving Verstappen and the Williams pair as the only no shows.

Unruffled by his encounter with Magnussen, Leclerc retakes the top spot with a 35.908.

Gasly goes third, ahead of Alonso, Perez, Ocon, Stroll and Norris, as Bottas uses the escape road at Turn 14.

Sargeant, Verstappen and Albon finally head out, the American getting it all wrong at Turn 5.

Verstappen goes third with a 36.172 on the softs, as Hulkenberg improves to fourth (36.277).

Quickest in the opening two sectors, Perez goes top with a 35.146 on the softs.

Albon goes sixth with a 36.372.

Verstappen crosses the line at 34.653, out-pacing his teammate by 0.493s. Meanwhile, Alonso improves to seventh with a 36.481.

Albon goes third on the softs (35.638), as teammate Sargeant posts a 36.587 to go ninth.

Currently 20th, Russell heads out on softs for the first time today. His teammate, who also has yet to try the red-banded rubber, is currently 19th.

Perez improves to 34.868 but remains second.

"I've got no front grip, I've got to box," says Ricciardo, who is currently 16th.

As Russell begins his first flying lap on the softs, having opted for an extra warm-up lap, teammate Hamilton heads out. While Russell goes third with a 35.106, Hamilton goes seventh with a 36.041.

Tsunoda is shown the black and white flag for crossing the line at the pit entrance.

As the qualifying sims get underway, a 36.004 sees Zhou go seventh, thereby demoting Hamilton.

Alonso goes third with a 34.939, ahead of Russell, Piastri and Hamilton, who has improved with a 35.516.

Sargeant goes fifth but is instantly leapfrogged by Bottas as the times begin to tumble.

On his second flying lap, Russell goes top with a 34.585.

Albon goes third with a 34.726, Sargeant confirming the pace of the Williams by going seventh with a 35.067.

A big lock-up for Hamilton as Zhou goes wide in Turn 1.

Sargeant improves to second (34.645), as Russell and Ricciardo go off at Turn 12 in quick succession.

Piastri goes top with a 34.491 as Verstappen is the latest to come to grief at Turn 12, the world champion almost collecting Ricciardo who was still trying to get back on track.

"Where am I down," asks Hamilton, before being given a whole list of corners where he is losing out.

Norris goes ninth, ahead of Magnussen and Stroll.

A 34.093 sees Russell reclaim the top spot from Piastri.

Albon has lost a rear wheel which rolls along the track before coming to a stop.

Replay shows he hit the barrier at Turn 12 ripping off the left rear tyre in the process.

The session is red-flagged with 4:40 remaining. It will not be resumed, which will not go down well with those drivers still in the process of fine tuning their cars on their qualifying sims, not least the Ferrari pair.

Russell is quickest, ahead of Piastri, Sargeant, Verstappen, Perez, Albon, Alonso, Hamilton, Bottas and Magnussen.

Norris is eleventh, ahead of Hulkenberg, Stroll, Ocon, Zhou, Leclerc, Sainz, Tsunoda, Gasly and Ricciardo.

Check out our Saturday gallery from Las Vegas here.