Hello and welcome back to our coverage of the season-opening Australian Grand Prix in Melbourne.

We'll be back tomorrow with live coverage of the third practice session and, of course, the all-important qualifying for Sunday's big race. Join us then.

So, Vettel tops his second session of the day as Red Bull impress ahead of the Australian Grand Prix in Melbourne!

There's the chequered flag and the session will be over shortly.

The debris is quite visible strewn over the track now. There's a lot of cleaning up to do overnight.

And now Webber spins! Although the Aussie manages to stay on the track and does no damage to his car.

Well, well, well. Mercedes have a lot of work to do tonight before tomorrow's action.

And look at this! Rosberg has stopped! Nightmare for Mercedes - both their cars will not finish this session.

Out comes the crane to lift the stricken Mercedes off the gravel.

Trouble for Hamilton! The Mercedes driver is in the gravel and it might well be another brake failure for the Briton! Not the best of starts for him today.

Nico Hulkenberg on Sauber team radio: "Guys, I'm picking up a lot of vibration."

Vettel's tyres are degrading badly and his lap times show that. Webber too, who pits.

Just 15 minutes left for the day now and still the Red Bulls are head of the class. Massa's still down in eighth, although he might have improved that had Gutierrez not impeded him earlier.

Massa and Gutierrez have a set-to with the Sauber man failing to look in his mirrors when exiting the pit lane. He should have let the Ferrari driver through then. The Brazilian raises a frustrated hand, his lap ruined.

Vettel is told by Red Bull team radio to make his tyres last. That's something we could be hearing quite often this season.

The teams will be looking now at how the cars perform on super softs tyres with heavy fuel loads on board.

After Vettel and Webber come Rosberg, Raikkonen, Grosjean, Alonso, Hamilton, Massa, Sutil and Hulkenberg.

So, the Red Bulls are on top with 25 minutes remaining this session. Vettel heads back out.

Lewis Hamilton improves slightly on his super softs with a time of 1m26.772 to propel him into seventh place.

Vettel does eventually oust his team-mate Webber from top spot with a clear lap of 1m25.908.

Vergne has a tasty spin but he manages to keep the car away from the walls and on the track.