Bayliss claimed the 20th pole of his career in Assen

Troy Bayliss was in a class of his own as he took pole for round four of the World Superbike Championship in Assen.

The 39-year-old Australian, who plans to retire at the end of the season, set a flying lap at the Dutch circuit of one minute 38.428 seconds for Ducati.

Japan's Noriyuki Haga was more than a tenth of a second behind for Yamaha with Spain's Ruben Xaus third.

Bayliss is on track to extend his 48-point lead at the top of the drivers' standings.

The Australian showed no side effects from a freak bicycle accident he suffered in Monte Carlo on Wednesday.

Bayliss escaped with cuts and bruises after his push-bike hit a manhole cover, and he was cleared after a precautionary medical.

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"There are always some niggling problems that you have being a racer," said Bayliss.

"But I'm feeling OK and there are no problems at all. This is a great position to start on Sunday."

His closest rival in the title race, Suzuki's Fonsi Nieto, could only finish ninth after the superpole session, three quarters of a second off the pace.

Australian Troy Corser qualified in fourth place and is now hoping to close the eight-point gap on second-placed Nieto.

Final grid positions for Assen:

1 Troy Bayliss (Aus) Ducati 1min 38.428secs
2 Noriyuki Haga (Jpn) Yamaha 1:38.546
3 Ruben Xaus (Spa) Ducati 1:38.587
4 Troy Corser (Aus) Yamaha 1:38.761
5 Max Neukirchner (Ger) Suzuki 1:38.840
6 Carlos Checa (Spa) Honda 1:38.864
7 Yukio Kagayama (Jpn) Suzuki 1:39.029
8 Jakub Smrz (Cze) Ducati 1:39.058
9 Fonsi Nieto (Spa) Suzuki 1:39.189
10 Makoto Tamada (Jpn) Kawasaki 1:39.307
11 Regis Laconi (Fra) Kawasaki 1:39.613
12 Michel Fabrizio (Ita) Ducati 1:39.859
13 Ryuichi Kiyonari (Jpn) Honda 1:40.000
14 David Checa (Spa) Yamaha 1:40.189
15 Gregorio Lavilla (Spa) Honda 1:40.377