Lewis Hamilton's lap on the softs is only good enough for second. He's three tenths of a second slower than Nico Rosberg, and that will be a boost to the German's confidence after a tough day yesterday.

Meanwhile, Felipe Nasr rumbles over the grass coming out of Turn 1. He's soon back on the track, no drama.

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Jenson Button loves Australia. He made his F1 debut here and has won the race on three occasions. Both he and Fernando Alonso are showing decent pace in this session, with the pair eighth and seventh fastest respectively, albeit on the super softs. Just the Mercedes, Ferraris, Red Bulls and Felipe Massa's Williams ahead of them.

Here come the Mercedes.

Nico Rosberg goes fastest of all so far in Australia as he zips round in 1:26.149 on the soft tyres - sixth tenths quicker than Daniel Ricciardo's time on the faster super softs.

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Swift work indeed by Haas and Romain Grosjean's first lap of FP3 is a 1:28.575 - set on the supersofts - putting him sixth.

Halfway through the session and everyone has been out on the track as Romain Grosjean finally gets in on the action, having had all that work done to repair his Haas.

Tom Clarkson
BBC Radio 5 live pit-lane reporter in Melbourne

"Wehrlein is the real deal, that is what we are being told. Mercedes have helped him get here, like they did with Michael Schumacher. I think surely we will see him driving for the works team in the future. 

"Everything is pointing towards Wehrlein being the next great German F1 driver."

P9 is very good for Pascal Wehrlein in the Manor. His best time of the session so far is a 1:31.481, four seconds off the pace. 

Meanwhile, Sebastian Vettel briefly had a spell at the top of the timesheet, having clocked 1:26.911 on the soft tyre, but Daniel Ricciardo slips back into P1 having popped in a 1:26.768 on the supersoft tyre.

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Andrew Benson
Chief F1 writer in elbourne

They say practice is meaningless. Well, that’s one of those “truisms” that is no longer true - at least when it comes to final practice. A corollary of the introduction of the new knock-out qualifying system is that the results of P3 could potentially define parts of the grid. 

As F1 director Charlie Whiting explains: “When we start qualifying, the drivers are put in the order of P3. And if more than one driver didn’t do P3 we go back to P2 etc, to establish the order in which they start qualifying. If, after seven minutes, the session gets stopped at that time, well, whoever is at the bottom of that list – it could be three drivers that haven’t set a time – the bottom one would go. That’s what would happen during the actual elimination process, that would establish the order.”   

Kimi Raikkonen, on softs, goes fastest with 1:27.560. That's 0.173 quicker than Daniel Ricciardo, who had set the previous fastest time on the supersofts. 

Impressive pace from the Ferrari.

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Almost a bit of drama as Nico Rosberg locks up just as he catches Kevin Magnussen and he just manages to avoid running into the back of the Manor, running straight on at the corner.

Meanwhile, Felipe Massa reports problems with his front tyres. He is on the supersofts.

Daniel Ricciardo, Daniil Kvyat and Sebastian Vettel are all back in the pits. The two Red Bulls were on supersofts, with Vettel on softs, Lewis Hamilton and Nico Rosberg are onto their 12th lap on the soft compound tyre.

Haas are still working away on Romain Grosjean's car, but Rio Haryanto's Manor was swiftly patched up. He has been out and currently has the 19th fastest time.