Ahead of today's second practice session, the air temperature is 14.5 degrees C, while the track temperature is 19.5 degrees. According to race control there is a 60% chance of rain over the next hour.

The big news since this morning is that Red Bull has chosen to retain Sergio Perez for 2022, thereby closing that particular door for drivers seeking a move up the grid.

The Mexican was sixth quickest this morning, 0.928s off the pace of Valtteri Bottas who edged out Max Verstappen by just 0.164.

Other than a couple of rookie mistakes from veteran Kimi Raikkonen it was an uneventful session, though not for Lewis Hamilton who finished a lowly 18th.

Other than a close encounter with Nicholas Latifi, Hamilton's problem appeared to be a lack of pace, the Briton eventually settling for a 'barn door' rear wing whilst his teammate opted for a much slimmer version.

Also looking strong this morning was Gasly along with the Ferrari pair, while Vettel, Norris and the Alpines rounded out the top ten.

Strangely, though it is not currently raining the session is declared wet, while earlier, when it was raining, it wasn't.

The lights go green and Bottas is the first to head out. He's sporting inters, despite a clear dry racing line.

He is soon joined by Raikkonen, Gasly and Norris.

"A couple of wet patches but definitely slicks," reports Norris, "it's too dry for inters," adds Bottas.

Indeed, Norris pits for hards as Russell also heads out on the white-banded rubber.

Norris gets things underway with a 48.219, as Latifi and Tsunoda head out on mediums.

Russell goes second with a 51.835 as Norris ups the ante with a 47.138.

A 48.429 sees Tsunoda go second, ahead of Ricciardo and Latifi, only for all three to be demoted when Leclerc posts a 47.149.

After 15 minutes, the only drivers still to appear are the title protagonists, Verstappen and Hamilton.

Ocon goes quickest (46.638) ahead of teammate Alpine as Hamilton and Verstappen head down the pitlane, both on mediums.

Stopping the clock at 46.198, Latifi goes top of the pile.

Quickest in the first two sectors, Bottas crosses the line at 44.513 to go top by 1.685.

However, the sky is getting increasingly dark.

Hamilton's first lap is only good enough for 15th (58.455), while a 45.127 sees Verstappen go second.

Next time around the Briton improves to 44.544 to make it a Mercedes 1-2, the world champion just 0.031s off his teammate's pace.

As Ocon complains of "quite a loss of grip", fans are taken on a lap of Spa by Alonso, his visor camera giving amazing insight from the driver's POV.

As the Williams pair switch to softs, so too do Bottas and Hamilton.

Russell immediately improves to 13th, though he is still off his teammate's medium pace.

Alonso goes quickest in S1, as the Mercedes pair don't appear to be pushing. That said, Hamilton goes quickest in S2, though a poor S3 sees him fail to improve. Teammate Bottas also fails to improve.

Alonso, on the other hand, goes fourth with a 44.953.

PBs in all three sectors for Stroll who goes 5th (45.180).

Ocon goes quickest in S1 as more drivers switch to the red-banded softs. Indeed, the only drivers still on mediums are the Ferrari pair.

Ocon goes seventh with a 45.302, albeit 0.4s down on his Alpine teammate.

Verstappen and Perez are among the last to head out on the softs.

Quickest in S2, Verstappen maintains the pace in the final sector, crossing the line at 44.472 to go quickest by 0.041s.

Out come the yellows when Ocon spins at Turn 14, leaving the Alpine facing the wrong way. Replay shows the Frenchman losing the rear end but doing well to keep it out of the barriers.

The session is red-flagged when Leclerc goes off and into the barriers at the exit to Les Combes. "Sorry guys," he tells his team.

With 14:00 remaining, it's: Verstappen, Bottas, Hamilton, Alonso, Gasly, Stroll, Ocon, Vettel, Norris and Perez.

The session resumes with ten minutes remaining, and there is a long queue of drivers eager to get back to work.

Soon there are 19 drivers on track, running a mixture of all three compounds.

Oh dear...Verstappen is off and in the barrier just after where Leclerc went off.

"It's finished," sighs the Dutchman as he climbs from the Red Bull which has suffered damage at the rear.

The session is red-flagged and will not resume.

Verstappen is quickest, ahead of Bottas, Hamilton, Alonso, Gasly, Stroll, Ocon, Vettel, Norris and Perez.

Sainz is eleventh, ahead of Tsunoda, Giovinazzi, Raikkonen, Ricciardo, Latifi, Russell, Leclerc, Mazepin and Schumacher.

Check out our Friday gallery from Spa, here.