Lewis Hamilton responded to Nico Rosberg’s clean-sweep of Friday practice times by setting a storming pace around Melbourne’s Albert Park in Practice Three.
There was little to choose between the Mercedes championship favourites on the opening day of the season, but on the soft-tyre simulations on Saturday morning the gap between the W06s grew to nearly a second in Hamilton's favour as the world champion uncorked an impressive lap of 1:27.867 to set the pace.
Rosberg’s earlier effort on the soft tyres had been somewhat less eye-catching and the German actually ended up behind countryman Sebastian Vettel in third place on the timesheet, as Ferrari suggested they could have the pace to challenge Williams for the second row in qualifying.
Williams pair Valtteri Bottas and Felipe Massa were fourth and fifth with Raikkonen half a second back on team-mate Vettel in sixth.
With Rosberg's final lap likely to represent an anomaly in the context of the remainder of the weekend, the battle for the first pole of 2015 looks likely to be a direct contest between the German and Hamilton.
Earlier in P3 and both Mercedes drivers had unusually been struggling with the handling of the W06 on the medium tyres, with Hamilton running across the road twice and Rosberg also experiencing difficulties at the apex of corners.
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March 15, 2015
Those problems, however, were nothing compared to some of their would-be rivals as Red Bull struggled with reliability and McLaren, again, for a semblance of performance.
On the back of the setback of losing one of Daniel Ricciardo’s four penalty-free engines on Friday, Red Bull ran into more problems when the Australian conked out on the exit of the pitlane. Team-mate Daniil Kvyat’s RB11 then suffered a fire in its Renault engine, ruling the Russian out of the qualy-style runs.
But while Red Bull are in danger of slipping down the top ten order, McLaren could prop up Sunday’s grid after their two cars proved the slowest of all the 18 runners in P3.
Remaining three and a half seconds off the pace, McLaren may only be saved the embarrassment of the back row if Manor finally run for the first time this weekend in qualifying. The returning backmarker again missed the session while they continued to work through the teething problems which kept them on the sidelines on Friday.