Ahead of today's second practice session the air temperature is 28.1 degrees C, while the track temperature is 37.7 degrees.
Not for the first time, Valtteri Bottas set the FP1 pace, while according to the Daily Mail, teammate Lewis Hamilton, "just trundled to just 19th", the tabloid not seeming to comprehend that the Briton was probably working on his own strategy.
Going by the various incidents, not least the crashes for Sainz and Latifi, we could be in for another eventful weekend. A number of drivers had offs including both Mercedes drivers.
Despite playing down Red Bull's chances, Verstappen was third quickest, albeit 0.654s off the pace.
However, it was the pace of Ricciardo that impressed, while teammate Ocon and the Points also looked strong.
In the moment before the start of the session, work continues on Sainz' car and also Latifi's.
The lights go green and Grosjean gets things underway. The Frenchman had a typically torrid morning session, punctuated by the usual expletive laden radio outbursts. He is subsequently joined by Norris.
"The new map is much better," says an uncharacteristically happy Grosjean, who goes on to post a 39.093.
As Giovinazzi, Bottas, Magnussen, Kvyat and Raikkonen head out, Norris posts 36.130.
Bottas (hards) goes quickest with a 36.065, while Magnussen posts 36.408 and Giovinazzi 37.857.
"Yeh, I've got a vibration," reports Raikkonen as he goes third with a 36.181.
On-board shows Bottas really struggling with the Mercedes.
Sainz heads out in the McLaren.
It was too good to last... "It was awesome on the out lap," says Grosjean, "but then it went bad."
Norris has his latest time deleted after exceeding the track limits at T2.
Meanwhile, Hamilton (mediums) goes quickest with a 34.890.
"The car is touching quite a bit on the straight," reports Magnussen.
Stroll spins at T13 but is able to continue.
Ricciardo shows that he has lost none of his pace over the lunch break, the Australian going second with a 35.341.
Verstappen posts 35.784 to go third, ahead of Bottas, Albon, Norris, Perez and Raikkonen.
Twenty minutes in and the Mercedes pair are first to switch to softs. Bottas immediately goes quickest in S1, maintaining the pace in S2. Meanwhile, Hamilton can only manage a PB in S1.
At the line Bottas posts 33.883, with Hamilton posting 33.786 moments later having made up a heap of time in the final sector.
Verstappen, currently fourth, complains of something wrong with his headrest. He is merely told to continue.
Having gone quickest in the first two sectors, Hamilton overdoes it at the infamous T13 and blows the lap. The Briton did well to avoid the barriers.
Moments later, Bottas makes no such mistakes and improves to 33.519 to go top.
In the Ferrari garage there is a lot of work going on on Leclerc's car. The youngster had previously reported 'pick-up' on his front-left.
Just over 35 minutes in and more drivers follow the Mercedes example and switch to the softs, Perez, Albon, Kvyat and Vettel among the first.
Stroll goes fifth with a 35.627 on the red-banded rubber.
Reporting a "big vibration", Hamilton pits, as Bottas has his latest time deleted after exceeding the limits at T2.
Russell goes eighth with a 35.575, with Ricciardo posting 34.577 to go fourth moments later.
Verstappen can only manage a 35.048 to go fifth, just ahead of Vettel, Gasly and Raikkonen.
Replay shows Verstappen having a nasty snap on the approach to T13, the Red Bull driver doing well to hold it all together. "Holy ****," he says, "I had no grip."
Ocon can only manage a 35.139 which puts him seventh, around 0.6s off his teammate's pace.
Norris improves to fourth with a 34.847 as Verstappen spins at T14.
Ocon is appraised of the time difference between he and his teammate, his engineer cryptically adding "obviously we know there are some differences there".
Sainz leapfrogs his teammate with a 34.723 to take fourth.
Hamilton switches back to mediums. Vettel follows suit.
With 30 minutes remaining, all 20 drivers are on track, the race sims in full flow.
Another lock-up and off for Hamilton at T13.
"What's going on here, it's like qualifying," says Russell, referring to the amount of on-track activity. "There's a lot of traffic at the last corner," adds Kvyat.
There's something in the cockpit," reports Bottas, "it's sticking to my left hand so I cannot steer." Cue mysterious music.
That said, there is nothing worse than grabbing hold of your mouse, only to find it is sticky due to a rogue sliver of marmalade that was on your hand.
While Bottas is now on hards and Hamilton mediums, the majority are on softs.
At which point it is finally confirmed that Stefano Domenicali will indeed replace Chase Carey as CEO of F1.
Ocon is told to be careful with his left-front at T4.
Unlike some of the recent races, tyre wear doesn't appear to be too much of an issue here, which begs the question, will we see some drivers attempt to qualify on the mediums tomorrow.
With Mercedes looking to have a 1s advantage here, that might be the only option available to those seeking to give the Black Arrows some sort of run for their money.
As the clock ticks down, a wide range of strategies at work with all three compounds being used.
While Mercedes looks strong the same cannot be said of Red Bull, with Verstappen 7th and Albon 12th, both over 1.5s off the pace.
As Sainz is told that his vibrations are looking better, Hamilton is told to pit after the Briton reports that his vibrations are "too big".
The session ends. Bottas is quickest, ahead of Hamilton, Ricciardo, Sainz, Norris, Perez, Verstappen, Leclerc, Ocon and Vettel.
Gasly is eleventh, ahead of Albon, Kvyat, Raikkonen, Latifi, Russell, Stroll, Magnussen, Giovinazzi and Grosjean.
Check out our Friday gallery from Sochi, here.