Hamilton fastest in Melbourne

Lewis Hamilton bounced back from his false start to the season to head a Mercedes one-two in second practice for the Australian Grand Prix.

Having arrived at the season-opener with expectations over his championship chances higher than for several years, Hamilton's start to the weekend was stopped even before it had even properly got going on Friday morning after his W05 ground to a halt on its out lap in P1.

However, while the Briton missed the remainder of the first session at Albert Park, the problem was traced to a relatively minor sensor calibration problem and Mercedes had Hamilton's car back out for the start of P2. And it was in the second session where Mercedes, for the first time this weekend, really showed the first signs of their expected pace advantage as Hamilton finished half a second clear of the field.

The 2008 title winner's fastest soft-tyre time of 1:29.625 proved to be 0.157s quicker than team-mate Rosberg's from slightly earlier in the session, with morning pacesetter Fernando Alonso back in the low 1:30s for Ferrari in third. Mercedes also regularly lapped in the 1:33s on their later higher-fuel runs, quicker than anyone else.

But while the strong pace of the W05 has been expected for weeks, it was arguably the performance of the hitherto troubled Red Bull RB10 that had caught the eye most by the end of the opening day of 2014 action as the World Champions followed up their encouraging P1 with more progress in the second 90 minutes of running.

While the widespread prognosis for Red Bull this weekend had been bleak after their torrid winter of repeat breakdowns and delays, Sebastian Vettel and Daniel Ricciardo's respective positions in fourth and sixth on the timesheet - and in particular the fact neither RB10 appeared to run into obvious unreliability - suggested the team had made a major breakthrough with the car in the two weeks since the final test.

The pace gap to Mercedes remained large - seven tenths of a second on the evidence of P2 - while Vettel regularly lapped half a second or more slower on his longer runs, but few were even expecting things to be that good just several days ago.

McLaren too, after a slightly low-key end to testing, can be pleased with their opening day after three-times Melbourne winner Jenson Button followed up his second-fastest P1 time with the fifth-quickest effort of P2.

After running strongly in the morning, Williams slipped back down the timesheet to eighth and 12th in the second session but technical chief Pat Symonds hinted to Sky Sports F1 that the Grove team - many pundits' dark horses for victory this weekend after an impressive winter - had run with higher fuel.

Last year's Melbourne victors Lotus, meanwhile, confirmed fears that they are in real trouble of not making it out of Q1 come Saturday - and perhaps not getting much further in Sunday's 58-lap race - after Pastor Maldonado missed the second session entirely and Romain Grosjean lapped four seconds off the pace, before wildly spinning off the circuit late on.

Some comfort for the Enstone team was that, after completing all of two laps with their two cars in the morning, Grosjean managed 12 in the afternoon - although the obvious trouble the Frenchman was having to plot a trouble-free course around the lap proved further cause for alarm.

Amazingly, things were even bleaker elsewhere though with fellow Renault-powered Caterham - who had proved the beleaguered French manufacturer's most reliable runner throughout testing - took to the track for just one lap as Marcus Ericsson's CT05 was hit by a hydraulics issue after its installation lap and Kamui Kobayashi by a fuel system problem.