Moto3 championshp leader Sandro Cortese beat Ajo team-mate Danny Kent to pole in an incident-packed Indianapolis session that saw two red flags.
The first stoppage happened when Aspar's Hector Faubel had a very violent high-speed at the final corner. Faubel escaped serious injury but has been taken to hospital for checks due to chest and back pain.
Kent then led much of the restarted session, but would not secure his maiden Moto3 pole as Cortese came through to depose him by just 0.083 seconds.
The duo's final pole shots were then halted when Alex Marquez had a similar accident to Faubel, causing a second red flag with 23 seconds left on the clock. It was Marquez's third fall of qualifying.
The stoppage interrupted many riders' final laps, but no one was quite as frustrated as Laglisse rider Efren Vazquez, who set a quicker time than Cortese moments after the red was shown, meaning it would not count. Rather than starting from pole, Vazquez will start seventh.
Cortese's title rival Maverick Vinales got himself onto the front row in third at the very end, with Luis Salom, Zulfahmi Zhairudden and Alex Rins filling row two.
Among the many other incidents in the session, Jack Miller sustained another broken collarbone in a fall. His bike then slid into Adrian Martin, taking the Laglisse rider down as well.
Pos Rider Team/Bike Time Gap 1. Sandro Cortese Ajo KTM 1m48.545s 2. Danny Kent Ajo KTM 1m48.628s + 0.083s 3. Maverick Vinales Avintia FTR-Honda 1m48.643s + 0.098s 4. Luis Salom RW Kalex-KTM 1m48.990s + 0.445s 5. Zulfahmi Khairuddin Ajo KTM 1m49.024s + 0.479s 6. Alex Rins Monlau Suter-Honda 1m49.045s + 0.500s 7. Efren Vazquez Laglisse FTR-Honda 1m49.074s + 0.529s 8. Romano Fenati Italia FTR-Honda 1m49.324s + 0.779s 9. Alberto Moncayo Laglisse FTR-Honda 1m49.332s + 0.787s 10. Jakub Kornfeil Ongetta FTR-Honda 1m49.334s + 0.789s 11. Miguel Oliveira Monlau Suter-Honda 1m49.397s + 0.852s 12. Alexis Masbou Caretta Honda 1m49.492s + 0.947s 13. Alessandro Tonucci Italia FTR-Honda 1m49.605s + 1.060s 14. Louis Rossi Germany FTR-Honda 1m49.610s + 1.065s 15. Jonas Folger Aspar Kalex-KTM 1m49.656s + 1.111s 16. Isaac Vinales Ongetta FTR-Honda 1m49.797s + 1.252s 17. Brad Binder RW Kalex-KTM 1m49.986s + 1.441s 18. Jack Miller Caretta Honda 1m50.056s + 1.511s 19. Alan Techer Technomag TSR-Honda 1m50.066s + 1.521s 20. Alex Marquez Ambrogio Suter-Honda 1m50.184s + 1.639s 21. Adrian Martin Laglisse FTR-Honda 1m50.249s + 1.704s 22. Jasper Iwema FGR-Honda 1m50.336s + 1.791s 23. Arthur Sissis Ajo KTM 1m50.412s + 1.867s 24. Niklas Ajo TT Motion KTM 1m50.443s + 1.898s 25. Niccolo Antonelli Gresini FTR-Honda 1m50.483s + 1.938s 26. Luigi Morciano Ioda Italia 1m50.936s + 2.391s 27. Danny Webb Mahindra 1m50.990s + 2.445s 28. Giulian Pedone Ambrogio Suter-Honda 1m51.073s + 2.528s 29. Hector Faubel Aspar Kalex-KTM 1m51.407s + 2.862s 30. Toni Finsterbusch MZ Honda 1m51.908s + 3.363s 31. Armando Pontone Ioda 1m52.070s + 3.525s 32. Kenta Fujii Technomag TSR-Honda 1m52.576s + 4.031s 33. Riccardo Moretti Mahindra 1m52.791s + 4.246s