Mercedes' Lewis Hamilton and Nico Rosberg justified their pre-race favouritism with the fastest times in practice for the season-opening Australian Grand Prix on Friday.
Former Formula One world champion Hamilton overcame mechnical problems in the first session to top the charts just ahead of his German team-mate Rosberg.
Rival drivers have tipped the Mercedes pair to fight it out for Sunday's race, given the team's superior pre-season testing and adjustment to sweeping technical changes.
A return to turbocharged engines, lower fuel loads, gearbox changes and new energy recovery systems are among significant rule changes for the new season.
Hamilton put in a scorching lap on soft tyres to post a best time of one minute 29.625, some 0.157secs ahead of Rosberg (1:29.782).
The Mercedes duo were the only drivers to go below 1:30, demonstrating an early edge over the rest of the field ahead of Saturday's qualifying for grid positions.
Ferrari's Fernando Alonso backed up from topping first practice with the third best time of 1:30.132, just over a half-second slower than Hamilton.
Four-time world champion Sebastian Vettel was fourth quickest in his Red Bull in 1:30.381, but a significant 0.756secs down on Hamilton.
It wasn't so enjoyable earlier in the day for Hamilton, the 2008 world champion, who came to a halt on his installation lap in the first practice session.
