Ahead of today's sole practice session the air temperature is 32 degrees C, while the track temperature is 46 degrees. It is bright and sunny.

Both of yesterday's sessions were compromised, the first by heavy rain at the start and the second ending early when Romain Grosjean tripped up over a loose drain cover.

While Red Bull, and particularly Ferrari, looked strong, Mercedes was at sixes and sevens, Toto Wolff claiming it was the worst Friday he can remember.

However, as Scarlet O'Hara said, "today is another day", or something like that.

With Bottas suggesting that the problems with the Mercedes could be down to the aero updates the team has brought here, he and Hamilton will this morning try different set-ups, the Finn understood to be sticking with the updates.

Grosjean's crash came just as teams were getting stuck into their high fuel race sims, and as a result of the 'interruption' there is every possibility that they will return to these this morning.

The lights go green and Gasly leads the way, the Toro Rosso rookie giving a good account of himself yesterday.

As was the case yesterday, Raikkonen complains of a vibration from his tyres.

Speaking of which, most drivers are on mediums, though the Toro Rossos are on softs and Raikkonen and Bottas are on supers.

No sooner has Gasly posted 37.083 than Raikkonen gets a little more serious with a 32.665.

"I have so much oversteer," claims Gasly who has a big slide in the final corner.

"Drain cover OK," reports Groundsman Grosjean.

Bottas, like Raikkonen on the supers, and with the new aero package, can only manage 33.364, which is 0.699s off the Ferrari driver's pace.

Ricciardo (softs) posts 33.607 to go third, ahead of Sainz, Gasly and Stroll.

A 33.324 sees Verstappen (supers) go third only to be demoted when Vettel (supers) posts 32.865. Hamilton, on the other hand, can only manage 33.370 on the supers.

"Stability is not good, really snappy," reports Gasly. "Understood, we have an explanation, box for a change," he is told.

Bottas improves to 33.094 but is still almost half-a-second off the pace.

Vettel improves to 32.686 but remains second, while Hamilton responds with a 32.650 to go quickest by 0.015s.

Ricciardo, the highest placed soft runner, improves to 33.432, but remains sixth.

Having gone quickest in S1, Ocon loses pace in S2. At the line he posts 33.547 which leaves his 8th, just behind his fellow Pink Panther.

Despite going quickest in S2, Hamilton fails to improve on his previous best.

Hulkenberg goes tenth with a 34.161 as, after 19 minutes, Wehrlein, Alonso, Magnussen and Vandoorne have yet to post a time.

Massa posts 34.063 to take tenth from Hulkenberg, losing a piece of bargeboard in the process after running wide.

Hamilton is told of a threat of rain. "I'll leave it to you as to whether you want to take your new tyres early," he is told.

A spin for Alonso in T15, McLaren, like Mercedes, running its drivers with different aero packages.

As the focus now switches to long runs, making up for yesterday's lost times, there are no significant improvements.

However, now on the supers, Ricciardo goes quickest in all three sectors, crossing the line at 32.091, 0.448s quicker than Hamilton.

At 'half-time', it's: Ricciardo, Hamilton, Raikkonen, Vettel, Verstappen, Bottas, Perez, Ocon, Alonso and Vandoorne.

Bottas improves to second (32.329), despite only being quickest in the final sector. His pace, which puts him ahead of his teammate, will only further confuse Mercedes in terms of which way to go with set-up.

The Ferraris are back on track, and no sooner has Vettel posted 32.042 than Raikkonen responds with a 31.880, the Finn quickest in the first and final sectors.

"That lap was horrible," complains Vettel.

Palmer is off at T15 and subsequently heads into the pitlane. "******* brake (pedal) went to the floor," he tells the FIA.

PBs in the opening two sectors but Hamilton can only manage 32.539 which leaves him fifth.

As Grosjean has a spin, Haas reports that Magnussen has an electrical issue.

Both Pink Panthers posts PBs in S1 however Perez loses pace in S2. Perez posts 33.472 with his teammate posting 33.290 moments later.

A big, big lock up for Grosjean which doesn't do his front-left any favours. The subsequent vibration is clearly visible.

Onboard with Vettel and the German is travelling very, very slowly. "Stop the car," he is told as he enters the pitlane. "What revs?" he asks. "Keep them as they are," comes the reply.

A spin for Verstappen in the final corner, the Red Bull driver opting to head into the pits. Relay shows a coming together with Palmer which resulted in the Dutchman picking up a puncture.

"******* idiot," says Palmer as the replay shows Verstappen appearing to turn in on the Renault driver and remove his nose in the process. The Briton was on a hot lap.

"He hit me," complains Verstappen. "What the hell!"

Probably one for the stewards.

Meanwhile, the session ends with no further significant improvements.

"I've got an engine problem again," warns Magnussen, who is guided back to the pits.

So, Ferrari leads the way, but that late scare for Vettel means qualifying, far less the race, is far from done and dusted.

Raikkonen is quickest, ahead of Vettel, Ricciardo, Bottas, Hamilton, Verstappen, Perez, Massa, Ocon and Vandoorne.

Alonso is eleventh, ahead of Stroll, Magnussen, Hulkenberg, Sainz, Gasly, Palmer, Grosjean, Ericsson and Wehrlein.

Check out our Saturday gallery from Sepang, here.