Corser benefited from the rain

The Australian finished behind Chris Vermeulen at Imola to go 55 points clear of compatriot Chris Vermeulen.

And the stewards' subsequent decision to cancel race two following a rainstorm put Corser out of reach with only the French Grand Prix remaining.

Only 50 points are still up for grabs for Vermeulen, who is considering a switch to MotoGP later this year.

In race one, Vermeulen edged Corser by 0.28 seconds to collect his fifth win of the season, with Japan's Noriyuki Haga taking third place on a Yamaha.

The decision to cancel race two came after an inspection by race officials and some riders, including Corser and Vermeulen.

It is the second Superbike title for 33-year-old, who added to his 1996 title.

He said: "That's the last way I really wanted to win the world championship.

"We've had a great year all year and I think results from the past have shown there was a pretty good chance we were going win it anyway.

"I'll be happy now to go to Magny-Cours in France and show that I should have won championship there, anyway."

Race one result:
1. Chris Vermeulen (Aus) Honda, 39 minutes, 35.789 seconds
2. Troy Corser (Aus) Suzuki, 0.28 seconds behind
3. Noriyuki Haga (Jpn) Yamaha, 6.31
4. James Toseland (GB) Ducati, 15.33
5. Steve Martin (Aus) Petronas, 49.63
6. Chris Walker (GB) Kawasaki, 50.07
7. Max Neukirchner (Ger) Honda, 52.17
8. Sebastian Gimbert (Fra) Yamaha, 52.38
9. Regis Laconi (Fra) Ducati, 57.83
10. Gianluca Viziello (Ita) Yamaha, 1:06.72

Race two cancelled due to heavy rain