Bayliss was in commanding form in Misano

Toseland finished in fourth and sixth place, struggling to come to terms with the pace of the front runners.

Race one saw Max Biaggi collide with Nori Haga as Bayliss finished ahead of Australian compatriot Troy Corser.

And Bayliss led from start to finish in race two, with Haga taking second place and Biaggi in third.

The Ducati Xerox rider was delighted to have won both races at the Misano track, the closest circuit to his team's Bologna headquarters.

"That's exactly what we needed," said Bayliss, who has 239 points in the championship. "In front of Ducati's local crowd too makes it pretty special.

"It's difficult to pass here but you have to wait for people to get tired and for tyres to go off. You see a mistake and you know you can go for it in the next corner."

Haga's crash in race one dented his hopes of closing the gap on Toseland and Bayliss in the championship.

Biaggi attempted to pass the Yamaha Motor Italia rider at a tight right-hander but only succeeded in taking out both riders and sliding into the gravel trap.

Yukio Kagayama took the final spot on the podium behind Bayliss and Corser.

World Superbike results, San Marino:

Race One:
1 Troy Bayliss (Aus) Ducati 38mins 52.856secs
2 Troy Corser (Aus) Yamaha 0:38:55.230
3 Yukio Kagayama (Jpn) Suzuki 0:39:01.821
4 James Toseland (GB) Honda 0:39:03.966
5 Roberto Rolfo (Ita) Honda 0:39:11.565
6 Lorenzo Lanzi (Ita) Ducati 0:39:13.323
7 Regis Laconi (Fra) Kawasaki 0:39:14.928
8 Ruben Xaus (Spa) Ducati 0:39:18.280
9 Max Neukirchner (Ger) Suzuki 0:39:23.747
10 Jakub Smrz (Cze) Ducati 0:39:30.580

Race Two:
1 Troy Bayliss (Aus) Ducati 38:43.506
2 Noriyuki Haga (Jpn) Yamaha 0:38:46.043
3 Max Biaggi (Ita) Suzuki 0:38:49.892
4 Yukio Kagayama (Jpn) Suzuki 0:38:52.411
5 Troy Corser (Aus) Yamaha 0:38:52.636
6 James Toseland (GB) Honda 0:38:57.473
7 Ruben Xaus (Spa) Ducati 0:39:00.214
8 Roberto Rolfo (Ita) Honda 0:39:00.287
9 Lorenzo Lanzi (Ita) Ducati 0:39:00.818
10 Max Neukirchner (Ger) Suzuki 0:39:16.571

Riders standings:
1 James Toseland (Gbr) Honda 260pts
2 Troy Bayliss (Aus) Ducati 239
3 Noriyuki Haga (Jpn) Yamaha 234
4 Max Biaggi (Ita) Suzuki 217
5 Troy Corser (Aus) Yamaha 182
6 Lorenzo Lanzi (Ita) Ducati 133
7 Ruben Xaus (Spa) Ducati 130
8 Roberto Rolfo (Ita) Honda 109
9 Max Neukirchner (Ger) Suzuki 100
10 Yukio Kagayama (Jpn) Suzuki 89

Manufacturers standings:
1 Ducati 284pts
2 Yamaha 277
3 Honda 274
4 Suzuki 233
5 Kawasaki 102