Hamilton cautious despite practice speed

The Briton, returning to the track where he made a sensational Grand Prix debut a year ago, posted a best time of 1:26.559 to finish nearly a second clear of his closest rival.

"It's great to be back racing and being here in Melbourne where I started my Formula One career only a year ago," said Hamilton. "It's always a special feeling to go out of the garage for the first time in practice at the start of a new season."

Despite his pace, Hamilton reckons their rivals are strong and did not want to judge McLaren's own form just yet.

"There was some good progress with the car, and we made the best use of the ever improving track conditions," he added.

"However our main opposition looks strong, but it's still too early to tell exactly where we are in comparison. All in all a good start to the Australian Grand Prix and the season."

Teammate Heikki Kovalainen was pleased with his first Grand Prix outing in a McLaren, despite finishing over a second behind Hamilton in fourth.

"It was a great feeling to drive out of the garage as a McLaren driver for the first time," he said. "I enjoy the professionalism of the team and how they operated during today's two sessions. It was a bit hotter than expected but that is just good practice for Malaysia.

"The wind was also something we had to take into consideration, but we made some good progress with the car. There was some graining of the tyres due to the dirty track conditions, but things improved as the circuit got more grip."