Ahead of today's opening session the air temperature is 32 degrees C, while the track temperature is 46 degrees. Humidity is 61%, however there is a 10% chance of rain.

In terms of updates, Red Bull has a new Floor Edge and Rear Wing Endplate, while Ferrari has a new Front Wing and Mercedes a new Front Corner.

Alpine has a new Sidepod Inlet, Cooling Louvres and Beam Wing, while McLaren has - wait for it - a new Front Wing Endplate, Sidepod Inlet, Halo, Floor Body, Coke/Engine Cover, Rear Corner, Rear Suspension, Rear Wing Endplate and Beam Wing, all of which are available to Norris this weekend, while teammate Piastri only has a few of them.

Alfa Romeo has new Floor Fences, Diffuser, Rear Corner and Front Wing, while Aston Martin has a new Rear Corner and Williams a new Front Wing.

Like McLaren, AlphaTauri has brought a raft of new parts including a new Floor Body, Floor Edge, Diffuser, Sidepod Inlet, Coke/Engine Cover and Rear Suspension.

Other than upgrades, McLaren and Williams both have revised liveries.

The lights go green and Stroll leads the way, followed by Lawson, Bottas, Alonso and Zhou.

As more drivers head out it is a mixture of the hards and mediums.

Soon all bar the Williams pair are on track.

Bottas gets things underway with a 39.308, while Alonso crosses the line at 40.337.

A 37.895 sees Norris go top, ahead of Sainz, Bottas, Perez and Alonso.

Gasly goes second and Verstappen third as the Williams pair finally head out.

"Something smells a little smoky, but I don't know..." reports Zhou. "We're checking," he is told.

Norris (mediums) ups the ante with a 35.782 as Sainz (hard) goes second with a 36.128.

Verstappen reveals that he is struggling with downshifts, the Dutchman claiming them to be aggressive.

Leclerc is currently third, ahead of Hamilton, Verstappen, Perez, Alonso and Hulkenberg.

Perez reports that he is struggling to see the apexes and may need to have his seat raised.

A 35.718 sees Sainz go top, the Spaniard buoyed by his performance at Monza.

Moments later however, Leclerc stops the clock at 35.683.

"Car feels a bit lazy," reports Albon as Alonso goes third with a 35.781.

Though just 0.098s off the pace, Verstappen reports a litany of issues with his car, as Norris splits the Ferraris with a 35.692.

On the hards, Hamilton goes top with a 35.571, as teammate Russell (hards) posts a 35.851 to go sixth.

As Norris reports unease with his car's balance, teammate Norris sets purples in all three sectors, crossing the line at 34.776.

Perez goes second with a 35.336, however he is subsequently demoted by Russell (35.005).

Ocon goes fourth with a 35.291, like pace-setter Norris he is on the mediums.

Around half-time, Gasly is the first driver to switch to the softs. The Frenchman is currently tenth, 1.422s off the pace. He subsequently posts a 34.980 to go second.

Piastri, Tsunoda and Magnussen also make the change to the red-banded rubber.

With the upgrade he says the team has been waiting all season for, Bottas remains seventh.

More and more drivers switch to the softs, Magnussen immediately going fourth (35.006).

The yellows are out in S2 and it takes some time before it is apparent why, it is a lizard.

Sainz gores quickest with a 33.944, as Russell goes second and Hamilton third.

Despite that new Stealth livery, one half of Norris' McLaren is absolutely smothered in flo-vis. Nonetheless, he goes quickest with a 33.522.

Leclerc is on a hot lap, quickest in the first two sectors he finally crosses the line at 33.350.

Moments later Verstappen goes second with a 33.746, 0.126s off the pace.

The Aston Martin pair, like their counterparts at Alfa Romeo, have yet to try the softs.

Perez improves to fourth ahead of Sainz, as Lawson goes twelfth.

"Eight-tenths, where has that come from," asks Hamilton of the gap to Leclerc. Told it is mainly in Turn 9 he subsequently closes the gap to 0.190s.

With 12 minutes remaining, there's another yellow. "Another lizard in Turn 9," reports Sainz.

Teammate Leclerc had been on a very hot lap until the pesky reptile made its appearance.

Having spent much of the morning languishing at the bottom of the timesheet, Albon improves to 12th with a 34.657.

"Another lizard, but a different one this time," reports Russell.

The session ends. A good positive showing for Ferrari, while McLaren will be delighted with those upgrades, even if they were only available to one driver.

Leclerc is quickest, ahead of Sainz, Verstappen, Norris, Hamilton, Russell, Perez, Alonso, Tsunoda and Ocon.

Stroll is eleventh, ahead of Gasly, Albon, Bottas, Magnussen, Lawson, Hulkenberg, Zhou, Piastri and Sargeant.

Check out our Friday gallery from Marina Bay here.