Toseland scrambled back onto the track and finished eighth

Troy Bayliss won the day's only race after the planned second race was cancelled as the conditions worsened.

Nori Haga's second place enabled him to close the gap on championship leader Toseland to 23 points with Max Biaggi, who finished sixth, dropping to third.

Toseland skidded out on lap three but rejoined the race in 18th place.

Troy Corser claimed the race lead soon after but Bayliss hit back straight away to reclaim the advantage which he never surrendered.

Australian Corser faded to third and Haga could not quite get on terms to make a bid to pass for the lead.

Toseland worked his way through the pack and was close to the top 10 when he benefited from crashes which took out several riders.

He had just moved up to eighth when both Bayliss and Haga lapped him.

Roberto Rolfo came in fourth, Regis Laconi was fifth on the PSG-1 Kawasaki and Biaggi was sixth.

Race one result:
1 T Bayliss (Aus) Ducati 46 mins 02.875 secs
2 N Haga (Jpn) Yamaha 46:04.910
3 5 T Corser (Aus) Yamaha 46:07.443
4 R Rolfo (Ita) Honda 46:52.914
5 R Laconi (Fra) Kawasaki 47:12.509
6 M Biaggi (It) Suzuki 47:23.857
7 L Lanzi (It) Ducati 47:35.936
8 J Toseland (GB) Honda at 1 lap
9 R Xaus (Spa) Ducati at 1 lap
10 M Neukirchner (Ger) Suzuki at 1 lap

World Superbikes standings:
1 James Toseland (Gbr) Honda 237pts
2 Noriyuki Haga (Jpn) Yamaha 214
3 Max Biaggi (Ita) Suzuki 201
4 Troy Bayliss (Aus) Ducati 189
5 Troy Corser (Aus) Yamaha 151
6 Lorenzo Lanzi (Ita) Ducati 116
7 Ruben Xaus (Spa) Ducati 113
8 Roberto Rolfo (Ita) Honda 90
9 Max Neukirchner (Ger) Suzuki 87
10 Regis Laconi (Fra) Kawasaki 62pts