Dani Pedrosa left it late at Austin to knock Honda team-mate Marc Marquez off top spot in the third MotoGP practice session.
Pedrosa lapped the Texan circuit in 2m04.408s, the fastest time of the weekend so far, to beat his compatriot by almost four tenths of a second.
That was six tenths fastest than the fastest time on Friday but still one second slower than Marquez managed in the pre-season test.
Marquez had bounced back from an early crash at Turn 13 to run fastest for much of the session but Pedrosa's late improvement left him no time to reply.
Jorge Lorenzo was a further half a second back in third, moving his works Yamaha above Cal Crutchlow's satellite Tech 3 machine with his last lap of the session.
Lorenzo made the gap to the Hondas much more respectable, having been more than a second behind for much of the session. His final effort hauled him above Crutchlow right at the last minute.
Stefan Bradl was fractionally ahead of Andrea Dovizioso in fifth, while Valentino Rossi had a low-key session on the second factory Yamaha and finished seventh fastest.
Alvaro Bautista, Nicky Hayden and Ben Spies completed the top 10 and claimed the final automatic spots in the pole shootout.
Behind them, Aleix Espargaro was the lead CRT machine, beating the satellite prototype bikes of Crutchlow's Tech 3 team-mate Bradley Smith and Andrea Iannone. The rookie pair will now have to fight through Q1 to join the rest of their 'class' in final qualifying.
Pos Rider Team/Bike Time Gap
1. Dani Pedrosa Honda 2m04.408s
2. Marc Marquez Honda 2m04.795s + 0.387s
3. Jorge Lorenzo Yamaha 2m05.295s + 0.887s
4. Cal Crutchlow Tech 3 Yamaha 2m05.630s + 1.222s
5. Stefan Bradl LCR Honda 2m05.908s + 1.500s
6. Andrea Dovizioso Ducati 2m05.963s + 1.555s
7. Valentino Rossi Yamaha 2m06.173s + 1.765s
8. Alvaro Bautista Gresini Honda 2m06.300s + 1.892s
9. Nicky Hayden Ducati 2m06.622s + 2.214s
10. Ben Spies Pramac Ducati 2m06.862s + 2.454s
11. Aleix Espargaro Aspar Aprilia 2m07.149s + 2.741s
12. Bradley Smith Tech 3 Yamaha 2m07.714s + 3.306s
13. Andrea Iannone Pramac Ducati 2m07.749s + 3.341s
14. Randy de Puniet Aspar Aprilia 2m08.405s + 3.997s
15. Yonny Hernandez PBM Aprilia 2m08.514s + 4.106s
16. Karel Abraham Cardion Aprilia 2m09.249s + 4.841s
17. Danilo Petrucci Ioda-Suter-BMW 2m09.409s + 5.001s
18. Hector Barbera Avintia FTR-Kawasaki 2m09.504s + 5.096s
19. Claudio Corti Forward FTR-Kawasaki 2m09.660s + 5.252s
20. Hiroshi Aoyama Avintia FTR-Kawasaki 2m09.675s + 5.267s
21. Colin Edwards Forward FTR-Kawasaki 2m09.698s + 5.290s
22. Michael Laverty PBM-Aprilia 2m10.109s + 5.701s
23. Bryan Staring Gresini FTR-Honda 2m11.017s + 6.609s
24. Blake Young Attack APR-Kawasaki 2m11.528s + 7.120s
25. Lukas Pesek Ioda-Suter-BMW 2m13.510s + 9.102s
26. Mike Barnes GPTech BCL-Suzuki 2m16.283s + 11.875s