Ahead of today's opening session, the air temperature is 16 degrees C, while the track temperature is 36 degrees.

As previously reported, Jak Crawford will replace Fernando Alonso in this session.

In terms of upgrades, Red Bull has a new Sidepod Inlet, Coke/Engine Cover, Floor and Rear Corner. To ingest higher pressure air to the sidepod inlet from upstream, the profile has been revised based upon simulation and initial running results yielding improved efficiency. As a consequence of the inlet changes, the sidepods have been revised to suit and offer an efficiency improvement for cooling and downstream surfaces. Given the braking energy demands of Suzuka, minor changes have been made to the rear wheel bodywork to suit the brake material requirements.

Ferrari has a new Front Corner and Floor Body. The circuit's braking duty allows Ferrari to introduce a smaller front brake duct geometry, trading off brake cooling for external aerodynamic performance benefits, while the floor body features a minor geometrical update not specific to this event, the reprofiling of the front floor stay fairing hopefully improving local flow features and returns floor performance gains.

Williams has a new Front Suspension. Compared to the launch car, a revised set of suspension claddings are available to package efficiently around the updated suspension structures. The incidence and profiles of the external claddings have been optimised to work effectively with the new internal suspension structures to ensure that the impact on the downstream flow field is mitigated.

Aston Martin has a new Front Wing, Front Wing Endplate and Floor Body. The chord of the 3rd front wing profile is shorter in conjunction with a reduced length strake. In conjunction with the front wing endplate change the modifications improve the load distribution at the outboard end of the wing. The new floor leading edge devices modify the spanwise generation of load across the width of the floor to improve performance.

Haas has a new Front Wing on which the SM actuation system has been simplified allowing smaller exposed geometries. The smaller linkages decrease blockage and consequently improve the airflow directed towards the rear of the car.

The Alpine has a new Front Corner, Rear Wing and Rear Wing Endplate. The front deflector has been redesigned to improve the management of the local flowfield, ensuring a consistent delivery of performance throughout the entire operating range, while local adjustments have been made to the rear wing to extract more performance out of it, both in Cornering and in Straight mode. The rear wing endplate has been redesigned to improve the flow conditioning at the rear of the car while also generating local load.

Finally, Cadillac has a new Diffuser Fence and Diffuser. The diffuser fence has been redesigned with a lower profile to enhance overall ride height behaviour and improve aerodynamic performance across the operating envelope. The trailing edge profile of the diffuser has been revised and optimized to enhance overall performance and increase overall rear aerodynamic load.

The pitlane opens and Hulkenberg leads the way, followed by Hamilton, Russell, Crawford and Leclerc. In moments almost all the drivers are on track, as the FIA carries out a VSC test.

There's a mixture of hards and mediums, though most have opted for the white-banded rubber.

Hamilton posts the first time of the weekend, a 37.256, but this is soon eclipsed by his teammate who posts a 37.246. Both are on the hards.

"My brakes are really cold," complains Hadjar, who adds that his car is "pulling", as he suffers a nasty snap in the final corner.

No sooner has Piastri posted a 34.053 than Russell responds with a 33.312.

A number of drivers are running aero rakes, Crawford's car appearing to have one of the biggest.

Leclerc improves to 32.883 and Piastri 32.812, only for Russell to respond with a 32.429.

Twelve minutes in and still no times from Bortoleto, Crawford, Ocon or Norris, while there appears to be an issue with Albon's car.

A 32.260 from Leclerc as Antonelli goes fourth and Hamilton fifth, albeit over a second off the pace.

As Lindblad goes quickest in S3, Antonelli improves to third with a 32.304.

Hadjar goes fifth and former teammate Lawson sixth.

Verstappen improves to seventh, his car smothered in flo-vis.

Lindblad goes sixth with a 32.891.

With 35 minutes remaining, Norris heads out. He posts a 34.595 but this is deleted for exceeding the track limits at Turn 14.

The Mercedes pair head out on softs, as Verstappen and Hulkenberg follow suit.

Russell raises the benchmark with a 31.755 while his teammate stops the clock at 32.032.

Antonelli improves with a 31.692 as Verstappen posts a 32.457 to go fifth, albeit 0.765s adrift of the Shanghai winner.

A 33.151 puts Norris eleventh, the world champion on the yellow-banded rubber.

Lindblad takes full advantage of the generous run-off at Spoon.

Quickest in S3, Hulkenberg goes sixth with a 32.798 as Russell reclaims the top spot with a 31.666.

Norris improves to sixth with a 32.517.

Albon brushes the barrier in the second Degner following a wild ride through the complex.

Currently thirteenth, Hamilton heads out on the softs.

Stroll is currently 5.2s off the pace and Crawford 5.4s.

"What's this idiot doing," asks Russell of Perez.

A 32.040 sees Hamilton go third, 0.374s off Russell's best.

Still on his original set of mediums, Norris improves to fifth with a 32.276.

Russell switches back to the hards, his teammate having closed to within 0.26s of his teammate.

It's only FP1 but we're already witnessing some silliness, with some drivers seemingly thinking it's Sunday. Unusually, for a practice session, we are seeing a lot of blue flags.

Ocon goes tenth with a 32.674 as the Red Bull pair switch back to mediums.

Another improvement sees Ocon go ninth, while his teammate is currently fourteenth.

Switching to softs, Norris goes third, 0.132s off Russell's pace.

"I don't know if he saw me," says Albon after clashing with Perez at the chicane. "Oh my God, he crashed into me," reports the Mexican.

Crawford has improved to 36.939, thereby demoting Stroll to 22nd.

The Albon/Perez incident has been noted. Indeed, it will be investigated after the session.

Verstappen runs wide in Spoon as Leclerc tries to pass Piastri who is all over the back of Gasly. Three abreast, again they seem to think it's Sunday.

"The Mercedes is so dangerous," complains Hadjar of a dithering Russell.

The session ends. Russell is quickest, ahead of Antonelli, Norris, Piastri, Leclerc, Hamilton, Verstappen, Lawson, Ocon and Lindblad.

Bortoleto is eleventh, ahead of Hulkenberg, Hadjar, Bearman, Gasly, Colapinto, Sainz, Albon, Perez, Bottas, Stroll and Crawford.