Ahead of one of the most pointless, unrepresentative practice sessions of the year, the air temperature is 28.7 degrees C, while the track temperature is 50.2 degrees.

We say pointless and unrepresentative because this session takes place in the afternoon, while it is still very, very, very warm, while qualifying and the race take place in the late afternoon, early evening, when temperatures are far cooler.

That said, that doesn't mean that teams will opt to sit it out, for, like Ferrari, they will use the session for simulation work.

Verstappen will not be running in the opening moments due to a hydraulic leak, Red Bull running different rear wings on its two cars.

Sainz and Norris are first out, followed by Giovinazzi, Raikkonen, Kvyat and Kubica. As ever, flo-vis abounds.

Six minutes in and all but the Mercedes pair have made an appearance.

Following that little burst of activity - if you can call an installation lap activity - it goes quiet for several minutes.

Verstappen heads out again, the Red Bull driver enjoying an absolutely clear track. Crossing the line at 1:33.085, the Dutchman gets the weekend underway.

Kubica and Sainz head out, followed by Norris, as Verstappen has a big wobble at T6.

Sainz posts 35.358, like Verstappen, the Spaniard is struggling on what is a very slippery track.

Hamilton and Bottas head out, twenty minutes into the session, as Kubica posts 36.857 and Norris 37.884.

Verstappen improves to 32.950 as Russell goes third with a 35.634.

Kvyat goes second with a 34.497, but moments later is demote when Hamilton stops the clock at 33.335.

As Bottas goes quickest in the first two sectors, Perez goes third with a 33.854. Bottas subsequently crosses the line at 32.340 to go top.

Twenty five minutes in and Gasly, Vettel, Leclerc and the Renault pair have yet to post times.

Out come the yellows as Stroll spins at T4. Replay shows he lost the rear after running over the kerb, and slightly clouted the barriers with his front wing. "Were the rears too cold," he asks. He is told to pit.

Leclerc goes second and Vettel third, both on the softs while pace-setter Bottas was on mediums. Verstappen also on the softs while Hamilton was on mediums.

A 32.299 sees Vettel go top, as Ricciardo foes seventh and Ricciardo tenth. Gasly the only driver yet to post a time.

"I lost the rear suddenly, a lot," reports Verstappen, following another wobble.

"What you won't see in this session is many long runs," admits Pirelli, "it's too warm for these to be of any significant use. Tyre degradation is also going to be higher than it will in race conditions, on the most abrasive track of the year."

Gasly's first lap sees the Frenchman go 18th (35.422), albeit on the hard rubber. Speaking of the hard - which is the hardest in the entire range - the quickest runner on the white-banded rubber is Sainz who is currently 14th (34.622).

Gasly reports that his car is suffering braking issues and "super-understeer".

At forty minutes, when the extra set of tyres have to be handed back, it's: Vettel, Leclerc, Bottas, Hamilton, Verstappen, Ricciardo, Albon, Hulkenberg, Magnussen and Kvyat.

Once again, Verstappen breaks the deadlock, heading out on to a clear track.

The Dutchman, still on softs, goes quickest with a 31.673, 0.074s quicker than Vettel's previous best.

Elsewhere, Gasly heads out, now on the softs, as Christian Horner confirms that the two Bulls are running different programmes.

The Frenchman goes quickest in S2, finally crossing the line at 31.815 to go third, having lost a little pace in S3.

Grosjean heads out to join the Bulls, the Frenchman currently 15th.

Slowly the drivers return to work, and soon Bottas is back on top, the Finn posting 32.328. Hamilton goes quickest in S2, but a mistake in the final corner means he can only manage 31.601. Early days, but the Briton appears to be pushing a little too hard.

Vettel and Leclerc are both on quick laps, the pair trading fastest sectors.

The German posts 30.617 to go top by 0.711, but Leclerc, despite a mistake in the final corner, responds with a 30.354.

PBs in all three sectors see Hulkenberg go eighth with a 32.040.

"The McLaren almost hit me in the side," reports Raikkonen, with all the passion of a man asked to tell you the time. The Finn is currently 12th, 2.257s off the pace, while teammate Giovinazzi is 15th.

In the Red Bull garage, Verstappen's car is up on its stand.

The qualifying sims over, attention now switches to longer runs, even though the race starts three hours later in the day.

A brief double-yellow but it is unclear why.

In the Mercedes garage, it appears that the rear wing on Hamilton's car is being changed, while in the Ferrari garage the left bargeboard on Vettel's car has been removed.

"Cool the rears, maintain front temperatures and cool rears," Stroll is told. The Canadian is currently 18th, 3.186s off the pace. He and teammate Perez are both on the softs.

With 12 minutes remaining, the Mercedes pair head out again, both on used softs. Gasly also.

More and drivers head back out, softs clearly the order of the day.

"A Toro Rosso just pushed me completely off the side," reports Raikkonen, albeit with a few added expletives. Albon being the guilty party.

A spin for Russell in T2 brings out the yellows again, the Williams driver appearing to have applied the power a little too early.

As Magnussen refuses to yield to Leclerc, teammate Grosjean has had an off over the kerb and damaged his front wing.

Elsewhere, Hulkenberg and Giovinazzi trip up over one another and ended up in a synchronised excursion.

The session ends, Leclerc leads a Ferrari 1-2, ahead of Vettel, Bottas, Hamilton, Verstappen, Gasly, Sainz, Hulkenberg, Kvyat and Raikkonen.

Ricciardo is eleventh, ahead of Magnussen, Albon, Perez, Norris, Giovinazzi, Grosjean, Stroll, Russell and Kubica.

Check out our Friday gallery from Sakhir, here.