By Ian Ransom

MELBOURNE (Reuters) - Record crowds are expected to hail local hero Casey Stoner at Phillip Island this weekend as he bids for a record sixth straight title in his last home Grand Prix, but injury and Jorge Lorenzo could spoil the Australian's farewell party.

Twice MotoGP champion Stoner's title defense has already been dashed by ankle ligaments damaged during the US Grand Prix in July, and the Honda rider will carry the still-painful injury onto the tricky coastal circuit where typically wet and gusty conditions are certain to prevail.

The circuit's owners have honored the Australian by naming the hairy turn three "Stoner's corner" and the rider has vowed to attack the track with his trademark aggression.

The injury, however, has worsened since his return at the Japan Grand Prix, where he finished a creditable fifth behind his team mate Dani Pedrosa.

"We're having a lot more trouble with it day-to-day, just getting around on it at all," Stoner said.

"But I don't think it will affect me any differently on the bike. The biggest moment I'm having at the moment is flexibility on the bike trying to get it working.

"Fortunately on this track there are not too many right hand corners that are so critical, so we should be a little more comfortable riding around here. The main fitness problem I'm having at the moment is endurance."

Despite a career marred by injury and illness, Stoner has enjoyed a long, uninterrupted reign at Phillip Island, and he underlined his mastery of the track on Friday by finishing top of the time-sheets after the first round of practice.

Stoner's time of one minute and 30.374 seconds was nearly a second faster than Yamaha's championship leader Lorenzo, who is locked in a two-horse race for the title with fellow Spaniard Pedrosa.

Lorenzo has had a chequered history at Phillip Island, and endured a nightmare weekend last year when he crashed in morning practice before the race and was rushed to hospital for emergency surgery on a mangled finger.

Lorenzo talked of a cautious approach to the weekend but cannot afford to be too cautious with Pedrosa only 23 points adrift in the title race and 25 up for grabs for a race win.

"It's only two races until the end, so more than ever we must be really concentrated and really focused on not making any mistakes," said Lorenzo, runner-up behind Pedrosa in Japan.

"Anyway, we have the opportunity to arrive in Valencia with the possibility to be world champion. We'll try to finish on the podium this time.

"It would be great (to win the title here) and we have to possibility to do it, but we are not going to make ourselves crazy just to do it."

Pedrosa, third fastest in the first round of practice, looked forward to the prospect of hunting down Lorenzo to set up a Spanish battle royale back home in Valencia.

"Riding here is always very special," he said. "There are many corners where you can steer the bike with the gas. There are some times when it's really cold, but sometimes it's wonderful to be here with this horsepower, especially into the last corner going onto the main straight and up the hill.

"It would be good (to have a title battle in Valencia), as there are two Spaniards fighting for the championship and the final round is in Spain. It's been a long time since I've been in this position, fighting until the end."

(Editing by Nick Mulvenney)