Marc Marquez clinched his ninth pole of the season in 125cc qualifying at Motegi.
The Spaniard fell to third in the championship when he was taken out at the first corner at Aragon a fortnight ago, but he gave himself the best possible chance of regaining ground by taking pole in Japan with a 0.417-second cushion over new points leader Nico Terol.
Terol is followed by his Aspar Aprilia team-mate Bradley Smith, with Marquez's Ajo Derbi team-mate Sandro Cortese completing the front row.
Aragon winner and title contender Pol Espargaro has had a tough weekend so far. After crashing twice in Friday practice, he lacked pace in qualifying and had to sit out the final part of the session with technical problems. That left him only seventh on the grid, behind top home rider Tomoyoshi Koyama and Esteve Rabat.
Simone Grotzkyj qualified a career-best eighth but crashed without injury at the end of the session. Newcomer Tommaso Gabrielli also fell, suffering a ferocious high-side at the final corner. The Italian was able to walk away despite the violence of his landing.
Red Bull Rookies Cup runner-up Danny Kent has joined the Lambretta team for the weekend and qualified 16th - the highest position the new bike has achieved all season.
Pos Rider Bike Time Gap
1. Marc Marquez Derbi 1m58.030s
2. Nicolas Terol Aprilia 1m58.447s + 0.417s
3. Bradley Smith Aprilia 1m59.026s + 0.996s
4. Sandro Cortese Derbi 1m59.102s + 1.072s
5. Tomoyoshi Koyama Aprilia 1m59.209s + 1.179s
6. Esteve Rabat Aprilia 1m59.660s + 1.630s
7. Pol Espargaro Derbi 1m59.873s + 1.843s
8. Simone Grotzkyj Aprilia 1m59.991s + 1.961s
9. Alberto Moncayo Aprilia 2m00.177s + 2.147s
10. Efren Vazquez Derbi 2m00.249s + 2.219s
11. Jonas Folger Aprilia 2m00.345s + 2.315s
12. Randy Krummenacher Aprilia 2m00.595s + 2.565s
13. Danny Webb Aprilia 2m00.634s + 2.604s
14. Luis Salom Aprilia 2m01.015s + 2.985s
15. Adrian Martin Aprilia 2m01.083s + 3.053s
16. Danny Kent Lambretta 2m01.109s + 3.079s
17. Takehiro Yamamoto Honda 2m01.285s + 3.255s
18. Johann Zarco Aprilia 2m01.411s + 3.381s
19. Marco Ravaioli Lambretta 2m01.660s + 3.630s
20. Jakub Kornfeil Aprilia 2m01.684s + 3.654s
21. Marcel Schrotter Honda 2m01.763s + 3.733s
22. Jasper Iwema Aprilia 2m02.071s + 4.041s
23. Louis Rossi Aprilia 2m02.240s + 4.210s
24. Sturla Fagerhaug Aprilia 2m02.309s + 4.279s
25. Sasuke Shinozaki Yamaha 2m02.521s + 4.491s
26. Hikari Ookubo Honda 2m02.816s + 4.786s
27. Zulfahmi Khairuddin Aprilia 2m03.316s + 5.286s
28. Syunya Mori Honda 2m03.592s + 5.562s
29. Lorenzo Savadori Aprilia 2m04.109s + 6.079s
30. Yuma Yahagi Honda 2m04.619s + 6.589s
31. Luca Marconi Aprilia 2m05.921s + 7.891s
32. Tommaso Gabrielli Aprilia 2m14.113s + 16.083s