Ahead of today's sole practice session, the air temperature is 27 degrees C, while the track temperature is 36 degrees. It is brighter than yesterday, with much less cloud.

The big news is that Pascal Wehrlein has withdrawn from the remainder of the event, the German feeling that he is not fit enough for a full race distance following his crash during the Race of Champions in January.

As a result his place will be taken by Ferrari reserve driver, 2016 GP2 runner-up, Antonio Giovinazzi. The Italian, you may recall, replaced Wehrlein in the opening test sessions at Barcelona.

Lewis Hamilton was quickest on both of yesterday's sessions - isn't he always - but it is today - late in this session, and certainly in qualifying - that we should get a far clearer of the early season pecking order.

Sebastian Vettel was second quickest, ahead of Bottas and Raikkonen, with the Red Bull fifth and sixth.

A number of drivers lost track time yesterday due to various issues, not least Jolyon Palmer who crashed in the Renault, therefore we are expecting it to be a busy morning.

Just moments before the green light a few spots of rain are noticed, but nothing significant.

For the third successive session, Grosjean is first out, followed by Haas teammate Magnussen. Bottas is the third driver to head out, the Finn keen to close the 0.5s (FP2) gap to his teammate.

More drivers head out, most on supersofts, though Bottas is on softs and Raikkonen ultras.

Having been 'asked' to remove its T-wing, Haas now has the aerodynamic 'aid' back in place.

Ricciardo posts the first time of the day, the Australian stopping the clock at 1:25.589. Massa subsequently posts 26.237 and Raikkonen 24.874.

Also on the purple-banded rubber, Vettel posts 24.308 to go 0.566sclear of his teammate.

Kimi stops at T13 with a left-rear puncture, thereby bringing out the yellows and subsequently the VSC. Despite the puncture, the Finn is confused as to why the car won't start.

"Why did my car stop when I tried to slow down?" he asks. "I felt the puncture, can I restart it?" He eventually gets going and heads back to the pits.

Unsurprisingly, having never driven this track and not sat in the Sauber since the opening test, Giovinazzi's first lap results in a 1:42. He then improves to 1:28.6.

Vettel improves to 23.989, just marginally off Hamilton's best from FP2, as Kvyat, in the increasingly impressive (and pretty) Toro Rosso, goes fourth with a 26.049. Moments later he is displaced by teammate Sainz (26.034).

After twenty minutes, only 12 driver have posted times, the Mercedes duo among those who haven't. Verstappen has just posted a 26.269 to go 7th.

On supers, Bottas splits the Ferraris with a 24.628, as teammate Hamilton heads out.

The cameras pick up on a very nice, but time-wasting slide from the Finn.

Alonso's first lap sees the Spaniard go 11th (26.988), teammate Vandoorne currently 14th (27.928).

On the supers, Hamilton posts 24.542 to go second by 0.553s to Vettel, which is approximately the delta we expect between the supersofts and ultras.

"I'm losing power," reports Palmer. "Box, box, box, box," comes the reply.

"I'm really struggling with the front-left," advises Grosjean as the cameras duly pick up on him running wide. The Frenchman is currently 8th (26.078).

By the looks of it, Vandoorne is another driver who is struggling with his front-left, the Belgian running wide in T14.

Ricciardo becomes the third driver to bold on the ultras, he posts 25.124 to go fifth, 1.136s off Vettel's pace.

Following his earlier issue, Raikkonen is back on track, on ultras, and immediately goes quickest, out-pacing his Ferrari teammate by 0.001s.

All eyes on Vettel who is back on track on a fresh set of ultras.

"I need to check my brakes," says an anxious Massa, who advises he will brake on the straight to test a long pedal. "Something is not correct, it's getting worse corner by corner," he tells his team.

Vettel is quickest in all three sectors, crossing the line at 23.380, the fastest ever lap witnessed here.

And now the fun begins, as the too look ahead to qualifying, the Mercedes duo switch to the softest compound.

Now on the ultras, unsurprisingly, Hamilton goes quickest in S1, while Bottas can only manage 23.859, almost half-a-second down on Vettel. Hamilton crosses the line at 23.870, to go third, also almost half-a-second down, having lost time in S2.

PBs in the first two sectors for Verstappen, who is on the supers, however he aborts the lap and pits. The teenager complains of "a lot of understeer".

With 13 minutes remaining, Hamilton, Ricciardo and Hulkenberg are the only drivers on track.

As was the case yesterday, the Force Indias are currently off the pace, with Toro Rosso and Haas appearing to be the current best of the rest.

Verstappen and Alonso have only completed 7 laps, while Vandoorne is on 9.

Out comes the red flag as Stroll clouts the wall at T10, appearing to damage the right rear suspension. The Williams crew faces a busy lunch hour.

With less than 9 minutes remaining, this also compromises the qualifying sims.

Appearing to be a case of youthful overenthusiasm, his father doesn't look too impressed as he watches the monitors in the Williams garage.

"Are you ok?" Stroll is asked. "Yeah, I'm ok, just the right rear," comes the dejected reply.

Despite the fact that the session is unlikely to be re-started, certainly for any meaningful running, a number of drivers, including Vettel, are still in their cars.

Indeed, the FIA confirms the session will not be restarted.

In the Ferrari garage, Seb and Kimi are introduced to actress Nicole Kidman, she towers over both of them.

Consequently, with a majority of drivers not having a simulation run, the session ends with Vettel quickest, ahead of Bottas, Hamilton, Raikkonen, Hulkenberg, Ricciardo, Grosjean, Sainz, Kvyat and Magnussen.

Massa is eleventh, ahead of Verstappen, Perez, Alonso, Vandoorne, Ocon, Stroll, Ericsson, Palmer and Giovinazzi.

Check out our Saturday gallery from Melbourne, here.