SACHSENRING, Germany (AFP) - Australian world champion Casey Stoner on Saturday lit up the German Grand Prix circuit to win his fourth consecutive pole position of the MotoGP season.

The 22-year-old, on a Ducati, will start Sunday's big race in the top slot, as he bids for a hat-trick of GP victories after back-to-back wins in Britain and the Netherlands.

The Aussie flyer, who smashed the lap record in Friday's free practice, posted a time of 1min 21.067sec, well ahead of last year's winner Dani Pedrosa, on a Honda, and American Colin Edwards of Yamaha.

It all bodes well for Stoner - chasing his 21st professional win - to banish last year's disappointment here when he came fifth despite starting on pole.

Next up was Italian Andrea Dovizioso, Spaniard Jorge Lorenzo and France's Randy De Puniet, who will start Sunday's race on the second row.

Italian five-time MotoGP world champion Valentino Rossi came home in the seventh fastest time, and will start a row behind, along with Nicky Hayden and Japan's Shinya Nakano.

Italian Marco Simoncelli set a new pole-position milestone in the 250cc on Saturday with a lap of 1 min 23.953sec to beat Spain's Hector Barbera into second.

The pair were separated by under two-tenths of a second, with Finnish series leader Mika Kallio a further half-second down.

DutchGP victor and poleman at the past three Grands Prix, Alvaro Bautista could only muster up the eleventh-fastest time of the afternoon.

Reigning 125cc world champion Gabor Talmacsi, last year's GermanGP winner, set a time of 1 min 27.552sec to take pole, pipping British boy wonder Bradley Smith into second.

Homeboy Stefan Bradl had been the fastest in morning practice, but crashed while chasing Talmacsi's time to end the day in third.

Standings leader Frenchman Mike di Meglio will start on the second row after posting the sixth-fastest time.