Ben Spies suffered a big accident with twelve minutes to go and was clearly shaken, but was able to return to the track in the closing minutes.
Cardion AB Ducati's Karel Abraham is returning to action this weekend, while Pramac Ducati's Hector Barbera has been ruled out by a broken leg in a training accident.
Barbera has been replaced by former MotoGP race winner Toni Elias, who split from the Aspar Moto2 team after Mugello.
The US GP also sees AMA rider Steve Rapp become the first wild-card entry of the season and first ever for the new CRT class.
Repsol Honda's Dani Pedrosa has one of the new RC213Vs available for Laguna Seca, while team-mate Casey Stoner has the new engine in the present chassis, as he had requested. Ducati are expected to debut 'some' new parts.
for pictures from the grand prix...
1. Jorge Lorenzo
ESP Yamaha Factory Racing (YZR-M1) 1m 20.554s
2. Casey Stoner
AUS Repsol Honda (RC213V) 1m 20.628s
3. Dani Pedrosa
ESP Repsol Honda (RC213V) 1m 20.906s
4. Ben Spies
USA Yamaha Factory Racing (YZR-M1) 1m 21.094s
5. Cal Crutchlow
GBR Monster Yamaha Tech 3 (YZR-M1) 1m 21.268s
6. Andrea Dovizioso
ITA Monster Yamaha Tech 3 (YZR-M1) 1m 21.539s
7. Alvaro Bautista
ESP San Carlo Honda Gresini (RC213V) 1m 21.732s
8. Nicky Hayden
USA Ducati Team (GP12) 1m 21.734s
9. Stefan Bradl
GER LCR Honda MotoGP (RC213V) 1m 21.753s
10. Valentino Rossi
ITA Ducati Team (GP12) 1m 22.544s
11. Randy De Puniet
FRA Power Electronics Aspar (ART CRT) 1m 22.886s
12. Aleix Espargaro
ESP Power Electronics Aspar (ART CRT) 1m 23.075s
13. Colin Edwards
USA NGM Forward Racing (Suter-BMW CRT) 1m 23.699s
14. Karel Abraham
CZE Cardion AB Motoracing (GP12) 1m 23.704s
15. Yonny Hernandez
COL Avintia Blusens (FTR-Kawasaki CRT) 1m 23.769s
16. Michele Pirro
ITA San Carlo Honda Gresini (FTR-Honda CRT) 1m 23.877s
17. Toni Elias
ESP Pramac Racing (GP12) 1m 23.898s
18. Mattia Pasini
ITA Speed Master (ART CRT) 1m 24.017s
19. Danilo Petrucci
ITA Came IodaRacing (Ioda-Aprilia CRT) 1m 24.227s
20. Ivan Silva
ESP Avintia Blusens (FTR-Kawasaki CRT) 1m 24.560s
21. James Ellison
GBR Paul Bird Motorsport (ART CRT) 1m 24.715s
22. Steve Rapp
USA Attack Performance (APR-Kawasaki CRT) 1m 26.887s*
* Outside 107% time (1m 26.192s).
Fastest practice time:
ESP Honda 1m 21.088s
Official Laguna Seca MotoGP records:
AUS Ducati 1m 20.700s
Fastest race lap:
AUS Ducati 1m 21.376s