Ahead of today's opening session, the air temperature is 22 degrees C, while the track temperature is 41 degrees.

Special rear wings to cope with the truly unique demands of this circuit will be in the spotlight this weekend, but so too is Mercedes, McLaren, Williams and a number of drivers, not least Max Verstappen.

While it is another couple of weeks before we get to some of the more 'typical' circuits, the likes of Mercedes, McLaren, Williams, Lewis and Max will not want to see another weekend pass by without a significant improvement in fortune.

As is so often the case, with the race and qualifying taking place significantly later in the day than this session, it will have little significance. However, for some of those mentioned above it offers the perfect opportunity for some testing before the show heads to Europe.

Vandoorne is first out, followed by Ericsson, Vettel, Magnussen and Alonso.

More and more drivers head out, a mixture of all three compounds, ultrasoft, supersoft and softs.

Five minutes into the session and with Verstappen and the Mercedes duo yet to appear, Raikkonen sets a blistering pace in the first two sectors before diving into the pitlane. The Finn, running on ultras.

Ricciardo reports "a bit of a power thing at the pit exit", his car running the traditional FP1 garden gate sensor device.

Finally, as Sirotkin heads out for a second run, he is joined by Verstappen and the Mercedes duo.

As drivers are warned of a slippery surface at T2, the cameras pick up on a small round foam object in the middle of the track.

"The routine in FP1 is installation laps to check systems, then general practice and data assessments, before more specific race and quali related works happens in FP2," Pirelli reminds us. "Drivers reporting a very green and slippery track."

Bottas posts 48.100 and Hamilton 47.563 as Mercedes gets straight down to business.

Hartley takes to the escape road at T8... he might be the first, but he won't be the last.

"Grip is very poor," warns Hamilton having improved to 46.465.

Hartley goes third (53.660)b but is demoted when Perez posts 48.704. Moments later, Verstappen posts 48.681. Stroll posts 49.276 to go fifth.

Verstappen gets up close and very personal with the barriers as he seeks to close the 0.878s gap to Hamilton. Indeed, the Red Bull driver posts 46.399 to go quickest by 0.066s.

Drivers are warned of more debris in T4. Said debris turns out to be the white paint that marks the track limits - as if the walls and barriers aren't enough - which is being ripped up as drivers push to the limit.

A 47.354 sees Ricciardo go fourth, ahead of Grosjean, Ocon, Stroll and Perez.

Ricciardo improves to second with a 46.336 as Raikkonen, on his first lap, posts 49.763 to go 11th.

Vandoorne complains about the "horrendous" smell of his car in the pitlane.

A 45.629 sees Hamilton leapfrog the Bulls to go quickest, however, while the Austrian cars are on softs he is on supers. Talking of which, Verstappen improves with a 45.559.

Vettel "surprised" that his rear-left is already looking "poor". He posts 50.012 to go 15th.

Told about his front and rear tyre temperatures, Grosjean responds: "Less talking please".

As Hulkenberg goes fifth with a 46.993, Ricciardo posts 45.369 to go top.

As Raikkonen complains of tyre issues, Verstappen has parked on track at T6. "I've stalled in first gear," he reveals, "what can I do?" What he omits to say is that he also hit the barrier after losing the rear of the car.

As the virtual safety car is deployed, despite being given of raft of instructions, the youngster is unable to get the car going again. In the garage, neither Helmut Marko or Jos Verstappen look too impressed.

Replays suggest that following a minor mistake the driver over-corrected and lost it, hitting the barriers with his left-front and damaging his wing in the process.

Under the VSC, after 37 minutes, it's: Ricciardo, Verstappen, Hamilton, Bottas, Hulkenberg, Stroll, Grosjean, Hartley, Alonso and Ocon.

Neither Ferrari driver is happy with their tyres, Vettel again complaining about his rears.

The VSC is withdrawn at just about the time the drivers would normally stop to hand back their extra set of tyres, which is convenient.

The McLaren duo break the silence, Vandoorne currently last in the standings 7.1s off the pace. He subsequently improves to 16th with a 49.545, while Alonso improves from ninth to sixth with a 47.436. Both are on the ultras.

A 46.861 sees Raikkonen go fifth, while Vettel, currently 18th, remains in his garage.

Vandoorne reveals that his gearbox suddenly went to neutral.

Magnussen and Gasly appear to think its Sunday, the Dane gets a tow and passes the Toro Rosso, only for the Frenchman to attempt to re-pass the Haas.

Hamilton gets it wrong at T2 after running wide in T1. Moments later, Sainz has a massive lock-up and runs wide in T3. Completing the sequence, Hartley gets it wrong in T1.

Verstappen quickest in the speed-trap, ahead of Grosjean, Perez, Hulkenberg, Ricciardo and Hamilton. Neither Ferrari makes the top ten.

Despite his previous mistake, Hamilton posts 45.200 to go quickest, as Vettel drops to last, 4.8s off the pace and only 7 laps completed.

Grosjean one of a number of drivers very unhappy with his rear grip... or lack of it. The Frenchman subsequently locks-up in T2, executing a perfect pirouette to get the Haas facing the right way again.

As Bottas and Ricciardo leapfrog Hamilton, the Finn posting 44.242, Raikkonen's session is clearly over, his Ferrari on its stand with the floor removed. A nightmare session for the Maranello team.

Worth noting that while the Mercedes duo continue on ultras, Ricciardo's best was on the supersoft.

Hulkenberg admits to a big lock-up, insisting that he can't use the tyres any more.

Outside the top four, the Panthers are currently best of the rest, ahead of Alonso and the Williams pair.

Still on the supers, Ricciardo goes quickest in S2, closing to within 0.035s of Bottas' best.

Vettel is back on track, on the ultras. He posts PBs in the first two sectors before easing off - due to double yellows - finally crossing the line at 46.840 to go 11th.

Ferrari crew form a wall in order to prevent prying lenses from seeing Raikkonen's stripped-down SF71-H.

On supers, Ocon posts PBs in the first two sectors, crossing the line at 45.237 to leapfrog Verstappen for fourth. Nonetheless, he is told he is losing time under braking in turns 2 and 3.

A big moment for Ericsson as he runs wide and over the kerb but somehow keeps it all together.

"What have we learned so far? There's not a lot of grip," admits Pirelli, "but that seems to suit some teams: look at the pace of Force India and Williams up to now.

Alonso gets it wrong at T2, the Spaniard having just left the pits on cold tyres and pushed a little too hard a little too early.

Perez not entirely happy with Magnussen's antics, the Mexican, already unhappy with traffic, further miffed by the Haas being on the racing line. Then again is anyone ever happy with Magnussen's antics?

Sirotkin takes to the escape road in T3 after a major lock-up. Shortly after Bottas has a similar moment in T1.

With minutes remaining the grip issue remains, Grosjean and Hartley the latest to make use of the escape roads as they run out of race track.

In the final moments, Perez improves to third with a 45.075, like Ricciardo and Ocon he is on the supers, while pace-setter Bottas was on the ultras.

The session ends. Bottas is quickest, ahead of Ricciardo, Perez, Hamilton, Ocon, Verstappen, Alonso, Sirotkin, Gasly and Vettel.

Stroll is eleventh, ahead of Hartley, Hulkenberg, Grosjean, Raikkonen, Leclerc, Ericsson, Magnussen, Vandoorne and Sainz.

While Verstappen is sure to dominate the headlines over the coming hours, it's worth noting that Ricciardo's best time was on the supersofts, as were the Force India's, while the Mercedes duo were on ultras. Then there are the obvious issues facing Ferrari.

Check out our Friday gallery from Baku, here.