Postpublished at 06:41 British Summer Time 26 March 2017
Tom Clarkson
BBC Radio 5 live commentator
It seems an extraordinary decision from Mercedes to bring in Lewis Hamilton when they did when track position is so crucial around Albert Park.
Vettel wins after leapfrogging Hamilton in pits
Hamilton second, Bottas third
Grosjean, Palmer, Ericsson out
Ricciardo, Stroll, Alonso also retired
Gary Rose
Tom Clarkson
BBC Radio 5 live commentator
It seems an extraordinary decision from Mercedes to bring in Lewis Hamilton when they did when track position is so crucial around Albert Park.
Sebastian Vettel is closing in on traffic ahead of him in the shape of Lance Stroll. Will Ferrari pit him? No. He's staying out.
He has a 23 second lead over Lewis Hamilton.
"This is race critical, we need to get past Verstappen," Lewis Hamilton is told.
"Repeat, repeat!" says a flustered Hamilton.
"We need to get past Verstappen."
"I don't know how you expect me to do that."
Hamilton is sounding very unhappy out there.
Mark Gallagher
BBC Radio 5 live Formula 1 analyst
Max Verstappen knows how to make his Red Bull extremely wide indeed as soon as he sees the Mercedes of Lewis Hamilton behind him.
Hamilton is not finding this race as plain sailing as he would have hoped.
Well, they say these cars will find overtaking difficult and we'll soon find out if that is true. Lewis Hamilton is closing in on the big guns now.
Mark Gallagher
BBC Radio 5 live Formula 1 analyst
This is a little bit of a strategy battle. Vettel is making hay with the clean air in front of him.
Ferrari going for overcut but Lewis Hamilton is the fastest man on the track right now. He does a 1:27.551 but has Max Verstappen ahead of him in fourth now.
Jolyon Palmer pits and it looks like that's it for the Renault.
Meanwhile, Sebastian Vettel is not responding to Lewis Hamilton's stop. He is staying out there.
Lewis Hamilton pits from the lead. The ultrasofts are swapped for softs and he is back out behind Antonio Giovinazzi.
The path ahead is clear for new race leader Sebastian Vettel to floor it.
Jack Nicholls
Radio 5 live Formula 1 commentator
The gap is down to 1.3 seconds at the front, no make that less than a second!
A couple of stops further down the field as Esteban Ocon and Antonio Giovinazzi pit for soft tyres.
Bad times indeed for Jolyon Palmer. He is plugging away but is having brake issues in the final sector.
"Arghh, same again," he says. "Keep going, Jo," is the message.
Mark Gallagher
BBC Radio 5 live Formula 1 analyst
It looked like pretty significant power unit issue for Romain Grosjean, if not a complete failure.
Tom Clarkson
BBC Radio 5 live commentator
You need to be tactical in how you use these two DRS zones here in Australia, There is not a long straight like there is in China where you can get a proper tow behind another car.
Race over for Romain Grosjean!
He pits with smoke pouring out of the rear of his Haas. He swiftly climbs out of the car as his crew do their thing with the fire extinguishers.
Big shame after what had been a promising showing this weekend.
Mark Gallagher
BBC Radio 5 live Formula 1 analyst
There is no doubt that leader Lewis Hamilton is responding every time that Sebastian Vettel puts in a faster lap. there is a good bit of cat and mouse going on at the front of the field.
Sebastian Vettel sets the fastest lap of the race and Lewis Hamilton immediately responds by going even faster. The Briton's lead is currently 1.8 seconds.
Race control confirm no further action from the stewards regarding the first lap contact between Marcus Ericsson and Kevin Magnussen.