McLaren pair Lewis Hamilton and Jenson Button set the fastest times in Friday's rain-affected second practice session for Formula One's Australian Grand Prix.
Hamilton's time of one minute, 26.801 seconds put him a quarter of a second ahead of teammate and British compatriot Button around the Albert Park circuit.
Red Bull's Mark Webber was third fastest, ahead of Mercedes' Michael Schumacher and Renault's Vitaly Petrov.
The best times were set in dry conditions at the start of the session, with some passing light showers preventing any improvement.
Hamilton had said Thursday that McLaren would use practice to learn how to set up the car for qualifying rather than the race, believing that the grid position would be the key to winning Sunday's race.
That explained the big gap from the McLaren times to some of its rivals. Ferrari's Fernando Alonso and Felipe Massa were 15th and 17th on the time sheets, more than three seconds off the pace, as they instead concentrated on their race set-up.
"It's only practice and I'm sure we're running less fuel than the Ferraris and Red Bulls, but we'll see tomorrow," Button said. "At the moment we've just got to focus on how the car feels, and it feels pretty good.
"As soon as I jumped into the car here I was reasonably happy with the balance and it's just got better throughout the day."
Schumacher outperformed Mercedes teammate Nico Rosberg for the first time in any practice, qualifying session or race this season, with the fellow German coming 10th.
"As often on Fridays, the performance is difficult to judge as everybody seemed to be on different programs," Schumacher said. "Having said that, I am quite happy with today's sessions, even if we did not run too much overall."
Toro Rosso's Sebastien Buemi was sixth quickest after he and teammate Jaime Alguersuari completed the most practice laps of any drivers.
Force India pair Adrian Sutil and Vitantonio Liuzzi were seventh and eighth respectively on the time sheets.
Red Bull's Sebastian Vettel lost control and slid off the track late in the second session, illustrating the dangers of pushing slick tires on a track marginally affected by rain. Intermittent spells of wet weather were forecast for both Saturday qualifying and Sunday's race.
Teething problems persisted for the new teams, with neither Hispania driver setting a time in the second session. Karun Chandhok's car came to a halt 100 meters after he exited the pits for his installation lap, while Bruno Senna never made it out of the garage because of a fuel pressure problem.
Virgin's Timo Glock suffered a gearbox malfunction that restricted him to nine laps, while teammate Lucas di Grassi did not set a time due a telemetry failure.
Despite the rain, the times in the second practice session outdid those of the early session, when Renault's Robert Kubica set the fastest time.
Sauber's Kamui Kobayashi had the most eventful first session. First he snapped off a front wing when he hit a cone positioned to prevent corner cutting, then later the replacement wing fell off under heavy breaking, spearing him across a gravel trap.
F1 rookie Petrov had a good day in terms of times, but not so good for his bank balance after being fined $7000 for speeding in the pit lane. The speed limit for practice is 60 kph rather than 100 kph usually in place for qualifying and race. A decision was taken Friday to keep the 60 kph limit for Saturday and Sunday after a request by the safety delegate.