World Superbikes championship leader Troy Bayliss recovered from a fall in race one to take victory in race two at the latest round in Assen.
Bayliss has claimed 10 wins so far this season
Bayliss, who failed to finish in the first race after slipping on the wet Netherlands track, came home ahead of Andrew Pitt and Fonsi Nieto.
The win extends his lead in the standings to 100 points.
Earlier, Briton Chris Walker secured his maiden World Superbikes victory in his 131st race.
The Kawasaki rider, 34, started in 13th place but braved the torrential rain to storm through and win a chaotic race in a time of 44 minutes, 23.501 seconds
Reigning champion Troy Corser, who was on pole for the opener, failed to finish either race while Pitt and Italian Michel Fabrizio were second and third in race one.
Fabrizio fought from 14th on the grid to claim third place aboard a DFX Honda while Walker's team-mate Nieto was fourth.
Norrick Abe claimed fifth on another Yamaha with Max Neukirchner a surprise sixth, the leading Alstare Suzuki after Corser and Yukio Kagayama both retired.
England's James Toseland struggled for speed in the wet and ended up eighth on his Winston Honda.
Bayliss now looks odds on to claim the title as he has a large gap over Toseland with just 150 points to play for.
Toseland finished ninth in race two to effectively end his title hopes.
Yamaha rider Noriyuki Haga, who was second in the championship going into the weekend, failed to finish both races.
Race one result:
1. Chris Walker (GB) Kawasaki 44mins 23.501secs
2. Andrew Pitt (Aus) Yamaha 44:28.466
3. Michel Fabrizio (It) Honda 44:47.631
4. Fonsi Nieto (Sp) Kawasaki 45:00.469
5. Norick Abe (Jpn) Yamaha 45:00.679
6. Max Neukirchner (Ger) Suzuki 45:00.825
7. Lorenzo Lanzi (It) Ducati 45:04.431
8. Roberto Rolfo (It) Ducati 45:05.358
9. Karl Muggeridge (Aus) Yamaha 45:16.883
10. James Toseland (GB) Honda 45:19.370
Race two result:
1. Troy Bayliss (Aus) Ducati 37mins 29.307secs
2. Andrew Pitt (Aus) Yamaha 37:38.649
3. Fonsi Nieto (Spa) Kawasaki 37:40.955
4. Yukio Kagayama (Jpn) Suzuki 37:42.050
5. Ruben Xaus (Sp) Ducati 37:42.118
6. Lorenzo Lanzi (It) Ducati 37:49.152
7. Alex Barros (Brz) Honda 37:58.548
8. Regis Laconi (Fr) Kawasaki 38:03.392
9. James Toseland (GB) Honda 38:11.420
10. Michel Fabrizio (It) Honda 38:21.122
Overall rider standings:
1. Troy Bayliss (Aus) Ducati 332pts
2. James Toseland (GB) Honda 232
3. Noriyuki Haga (Jpn) Yamaha 230
4. Andrew Pitt (Aus) Yamaha 197
5. Troy Corser (Aus) Suzuki 193
6. Alex Barros (Brz) Honda 175
7. Yukio Kagayama (Jpn) Suzuki 139
8. Chris Walker (GB) Kawasaki 123
9. Lorenzo Lanzi (It) Ducati 115
10. Fonsi Nieto (Sp) Kawasaki 112
1. Suzuki 379pts
2. Honda 300
3. Ducati 293
4. Yamaha 244
5. Kawasaki 145
6. Petronas 25