Ahead of today's second session, the air temperature is 34 degrees C, while the track temperature is 57 degrees. It remains bright and sunny and very, very warm.

In terms of upgrades, almost all of which are circuit specific, McLaren has a new Rear Wing and Floor Furniture. The high isochronal rear wing has been modified to deploy the flap to an alternative position in straight line mode in combination with a less loaded beam wing, resulting in a larger reduction in drag. In other words, the so called H-Wing, McLaren's version of the Macarena. A small modification to the floor furniture, will result in better flow conditioning and resultant improvement of aerodynamic performance of the floor as well as drag reduction.

Mercedes has a new Rear Wing and Front Bodywork. Removing the rear wing winglets reduces assembly camber shedding local downforce and drag at a ratio appropriate for Monza low downforce (L/D), while the mirror stay trim reduces local camber and loading, shedding local downforce and drag at a ratio appropriate for Monza.

Red Bull has a new Rear Corner, Floor Body, Exhaust Tailpipe and Front Wing. To improve reliability of the rear wheel bodywork assembly, the gaitor providing an aerodynamic seal has been changed to reduce the probability of splitting from the wishbone and now removed winglet junctions. Meanwhile, in seeking to validate an alternative geometry, the edge profile has been revised for evaluation in Monza. The new geometry will revise the flow to create more local load with improved aerodynamic stability. In order to operate the power unit reliably around the Monza circuit with its unique demands, the tailpipe bracket has been trimmed to offer less blockage. Finally, a trimmed front wing end plate dive-plane is available for evaluation in Monza which aims to improve downstream load from the floor.

Ferrari has a new Floor Board, Mirror Stay, Rear Corner and RV Tail. Seen as a package, the primary aim of these modifications has been to adapt to Monza's peculiar characteristics and car aerodynamic efficiency requirements. All the steps have been targeting aerodynamic drag saving, coming along with downforce reduction as a natural consequence, but in a favourable ratio for this track.

Williams has a new Halo, Front Wing and Floor Body. The Grove outfit has modified the local pressure distribution around the driver cockpit area. This results in a downstream flow field change which benefits efficiency levels specific to Monza. The rearward element on the front wing assembly has been modified to suit the balance requirement of the circuit. Finally, a local trim has been applied to the floor board geometry. This is a further circuit specific change, altering the balance between downforce and drag at the front of the main floor.

Racing Bulls have a new Rear Wing and Exhaust Tailpipe. The rear wing changes facilitate increased flap travel in Straight Mode. This allows an efficient drag reduction which suits the nature of the circuit. The tailpipe updates improve the flow management around the centreline of the car, allowing the floor and rear wing to perform more efficiently.

Aston Martin has a new Front Suspension and Floor Edge. The external fairing for one of the front suspension members has been modified to improve alignment with the onset flow, while the geometry in front of the rear tyre has been modified to improve the airflow to the underside of the floor increasing load generated in this area.

Haas has a new Floor, Bodywork and Rear Corner. The floor update focuses on optimising the main expansion region and associated side geometry to improve airflow behaviour throughout the floor. The revised design increases floor efficiency, delivering a net gain in overall aerodynamic performance and downforce production. The revised bodywork has been developed in conjunction with the new floor design to maximise the aerodynamic benefit of the floor package. The updated geometry improves airflow management around the car while providing the necessary cooling performance for all operating conditions. The aerodynamic changes introduced by the new floor and bodywork package alter the flow structures reaching the rear corner region. To accommodate these changes and maximise the benefit of the update, the rear corner fairings have been re-optimised and the rear drum deflectors realigned, improving local flow management and overall aerodynamic efficiency.

Alpine has a new Front Wing Endplate and Rear Wing. As part of the French team's front wing development program, the vane has been redesigned to increase the local load and improve local flowfield, while the SM pod on the launch rear wing has been adjusted to better suit the low drag nature of the Monza track.

Cadillac has a new Forward Floor and Diffuser Vane. The revised forward floor board stay geometry improves flow conditioning to the rear of the car, increases structural stability of the component and improves overall aerodynamic load at the rear of the car, while a small vertical turning vane has been added to the inner trailing edge of the outboard diffuser sidewall, which improves aerodynamic performance in the outer floor channels and increases the load at the rear of the car.

Audi is the only team that hasn't brought any upgrades or updates.

Leclerc led a Ferrari 1-2 in FP1, he and his teammate appearing to benefit from the new engine the Maranello squad has brought here. Even more impressive however is the fact that both drivers posted their best times on the medium rubber, while those behind - Russell, Lawson and Antonelli were on softs.

Of course, with Antonelli set to start Sunday's race from the back of the grid after taking on a new engine, the youngster is focussing on Sunday's race not qualifying, though he looks set to help his teammate with a tow during tomorrow afternoon's session.

Also looking good earlier were Lindblad, Bortoleto and Colapinto.

There were four reserve drivers on duty earlier, which means that this afternoon Verstappen, Albon, Perez and Gasly get their first taste of the Autodromo, the Frenchman no doubt fired up after learning earlier that he has been stripped of his third-place finish in Monaco.

The lights go green and Bortoleto leads the way, followed by Bearman, Bottas, Colapinto and Bottas.

It's a mixture of mediums and hards, though Stroll is on softs.

Of the first wave Bortoleto is quickest (24.666), until Leclerc (medium) responds with a 23.472.

Antonelli (hards) stops the clock at 23.417 as Russell goes third (23.625).

Ten minutes in and Perez and Alonso have yet to appear. The Mexican's car was driven by Herta earlier, but the American only completed a couple of laps before suffering a hydraulics issue.

Russell goes top with a 23.202.

"This is really bad, no downforce at all on the car," complains Verstappen, the Dutchman currently tenth, 1.302s off the pace.

He subsequently improves to eighth with a 23.950, as Lindblad goes third with a 23.468.

"What the hell is this guy doing, it's dangerous," says Norris after being forced to take a detour at the first chicane as Stroll seems not to see him as he leaves the pits.

The incident has been noted.

"The car has no grip in low speed," says Verstappen as he lists a number of corners. "It's like driving on ice."

"What an idiot," complains Antonelli of a significantly slower Bortoleto, "what a complete idiot!"

The Mercedes pair head out on softs, Antonelli subsequently posting a 22.700 to go top.

The Stroll/Norris incident is to be investigated.

Antonelli pits leaving his teammate and Lawson to have the circuit to themselves.

Quickest in the opening sector, Russell crosses the line at 22.686.

With half-an-hour remaining the Ferraris, Red Bulls and McLarens head out on the softs.

Colapinto improves to fifth with a 23.619 as Sainz goes quickest in S1.

Tsunoda goes third and Lindblad fourth, but are demoted when Leclerc crosses the line at 22.679, 0.007s up on Russell.

Hamilton can only manage fourth, 0.337s off the pace.

Sainz, and then Gasly, go quickest in S1, but subsequently lose pace over the remainder of the lap.

A 22.559 from Russell as Norris goes fourth with a 22.943.

As Bortoleto has a big moment in the first chicane, Antonelli heads out on hards.

Verstappen fails to improve on seventh, and remains 0.818s off the pace, while teammate Lawson is currently eleventh.

Piastri improves to fifth as Bearman goes eighth.

Ocon, who, unlike his teammate, doesn't have the new Ferrari engine, can only manage 18th, a second slower than the Briton.

With twelve minutes remaining, McLaren send out Piastri and Norris together, both on the hards.

The Ferrari pair are back on the softs. Leclerc subsequently enjoying a 180 as he exited the second chicane.

Verstappen, Antonelli and Tsunoda are lapping almost as one, with Hamilton closing in. It could well be that the drivers are looking ahead to Sunday and energy usage.

"Is everything OK with my engine," asks Bortoleto. Sadly it is not, and he is ordered to pit.

"The car is jumping a lot more now," reports Verstappen.

Colapinto does well to hold it all together as he runs wide exiting Ascari.

"This understeer is unbelievable," says Antonelli as Alonso has a major lock-up in Ascari.

The session ends as Russell, feeling a vibration on his front suspension, asks his team to check the car.

Russell is quickest, ahead of Leclerc, Antonelli, Norris, Hamilton, Piastri, Lindblad, Bearman, Verstappen and Tsunoda.

Colapinto is eleventh, ahead of Lawson, Hulkenberg, Gasly, Bortoleto, Albon, Sainz, Ocon, Alonso, Perez, Bottas and Stroll.

One gets the feeling, looking back at both sessions, that neither Mercedes nor Ferrari is actually showing its full hand, and that could include McLaren.

However, there is a long way to go, besides which, because overtaking is possible here, qualifying is not vital.

That said, we do expect to see teammates helping one another, while the opening couple of laps look set to be a yo-yoing fest.