Australian rider Casey Stoner's Phillip Island farewell is off to a flying start.
Aiming for his sixth successive win at the Australian Grand Prix, Stoner was fastest in opening MotoGP practice by nearly a full second.
He set an early flying lap of one minute 31.046 seconds before light rain interrupted the 45-minute session at Phillip Island.
But after the rain cleared, the Honda rider again put down a sizzling marker - his 1:30.374 lap faster than world championship contenders Jorge Lorenzo (1:31.279) and Dani Pedrosa (1:31.533).
Stoner is racing just weeks after surgery on a serious ankle injury, competing in his last Australian GP before retirement at the end of the season.
Yamaha rider Lorenzo leads Honda's Pedrosa by 23 points in the championship.
They are the only two riders who can win the crown with two races remaining.
Lorenzo has promised he won't "go crazy'' at Phillip Island this weekend in his attempts to wrap up the title ahead of fellow Spaniard Pedrosa, even though he could secure it with the right mix of results at the second-last race of the year.
"It would be great and we have possibilities (to wrap up the title at Phillip Island), but we're not going to go crazy to make it here,'' Lorenzo said.
"The most important thing is to make it.
"More than ever we must really concentrate and focus and not make any mistakes.''
Australian Kris McLaren, making his MotoGP debut as a replacement rider for the Avintia team, was slowest of the 20 riders with a 1:40.657 fastest lap.
A second practice session is scheduled for later on Friday ahead of Saturday's qualifying and Sunday's race.