Having failed to lead a single track session last time out at Estoril, Valentino Rossi began the Australian Grand Prix in dominant form during Friday practice at Phillip Island - while his team-mate and title rival Jorge Lorenzo fell.

Rossi, who holds a reduced 18 point lead over Lorenzo with three rounds to go, returned to the top of the timesheets after 15 minutes of the hour and was uninterrupted thereafter.

Although the reigning six time MotoGP champion's advantage was cut to just 0.135sec by home hero Casey Stoner, on the Ducati star's last lap, Rossi remained almost half a second ahead of third place Dani Pedrosa (Honda) and a crucial 1.045sec clear of Lorenzo in sixth.

All in all, a good day for the Italian - who is aiming to wrap up his ninth world title in next weekend's Malaysian Grand Prix, thereby avoiding a final round showdown at Valencia.

"Today we made a great start," he confirmed. "We were concentrated and strong and I am really happy to start in front here at Phillip Island, which is somewhere that I love to ride.

"We were able to get a lot done in the practice session and try many different things and I was able to ride just how I wanted to.

"We can definitely improve more - even though we already have a good pace we will continue to work tomorrow and try to find a little bit more, but for the first day I think we can be very happy about our work," he concluded.

After heavy rain for the last two days the coastal track was granted a reprieve today as the sun shone brightly throughout the MotoGP session.

"The weather has helped us today; it's always good to have the first day in the dry," stated Rossi's Fiat Yamaha team manager Davide Brivio. "Of course now we hope that it stays like this so that we can continue our work tomorrow, but if not then we will be ready for the rain too."