Jacque attacks to bring Chesterfield 1-2.

Frenchman Olivier Jacque was the only one of the GP250 frontrunners to break below 2mins 4secs in second qualifying, and duly put his Yamaha on pole position for the Czech Grand Prix.

The Chesterfield-backed rider had to wait until the closing minutes of the session to record his faster time, but duly edged Tech 3 team-mate Shinya Nakano out of top spot with a perfectly judged lap. Jacque's climb from third assured the silver and yellow bikes of their third one-two start this season, and completed a personal hat-trick for the rejuvenated Frenchman, who had to miss much of last year through injury.

''It was pretty hard to improve my time yesterday and today,'' the championship leader admitted, ''but I think I found an advantage by starting the session quickly. I was able to try many set-ups and tyres, and am confident for the race tomorrow.''

Overnight pole-sitter Nakano was understandably disappointed at being dumped back to second, and blamed the rising track temperatures for his inability to find time. The Japanese was never in danger of being caught by third placed Ralf Waldmann, however, as the German Aprilia rider held onto his front row spot despite not improving on yesterday's 2mins 03.927secs.

Tohru Ukawa did improve, however, knocking Marco Melandri's Aprilia off the front row as he got a tow at the end of the session. The pair ended up swapping places, with the now number 35-liveried Melandri dropping to fifth after only finding a small improvement in the hour.

He will be joined on row two by fellow Italian Franco Battaini - who did not improve at all, Jamie Robinson, who crashed early on and also failed to find time despite rejoining the session, and Daijiro Katoh, who hauled himself up from 16th to eighth. Second Briton Jay Vincent took ninth, but Adrian Coates could only manage 29th after losing the entire session on Friday to gearbox problems.

Klaus Nohles, on the second Aprilia Germany bike dropped from row two to row three, while Naoki Matsudo and Ant West will line up one row apart after finishing the session 12th and 16th respectively.

Full results will follow shortly....

Leading qualifiers - GP250.

1. Olivier Jacque Yamaha 2mins 03.673secs
2. Shinya Nakano Yamaha 2mins 03.686secs
3. Ralf Waldmann Aprilia 2mins 03.927secs
4. Tohru Ukawa Honda 2mins 04.019secs
5. Marco Melandri Aprilia 2mins 04.041secs
6. Franco Battaini Aprilia 2mins 04.749secs
7. Jamie Robinson Aprilia 2mins 05.244secs
8. Daijiro Katoh Honda 2mins 05.323secs