The 27-year-old Californian was quick throughout the session and edged out his Kawasaki ‘wild-card’ rival right on the final lap with a time of 1M25.248, one-tenth of a second off the outright circuit record. “I sure showed that Eric guy the way round today!”, said a delighted Bostrom after qualifying. “I’ve still got a bit of work to do on the tyre situation, but the bike was working really well and the team did a good job. Seriously though, it was nice to have Eric setting the pace with me this afternoon, we ’ll see how it goes tomorrow”.

Troy Bayliss (Ducati Infostrada) was right behind the leading duo as he powered his Ducati 996R Factory around the 3.610 km circuit in a time of 1M26.075 to take third slot. The 32-year-old Australian’s time came in the last couple of minutes of qualifying as he moved up from a provisional eighth. “That wasn’t so bad, it’s the fastest I’ve ever gone around here”, declared Bayliss. “I hope to find a little bit more tomorrow because the set-up is coming better all the time. Despite the fact that I’ve got a couple of local boys in front of me, I’m feeling pretty good”.

Ducati rider Ben, a winner at the last round at Misano, San Marino, ended the day in provisional pole position with Kawasaki wild card rider Eric second, after both came within 0.4s of the lap record at the 2.24-mile circuit near Monterey.

Championship leader Troy Bayliss finished third with reigning champion Colin Edwards fourth. Edwards commented: "We arrived here with a good idea for machine set-up, tried to improve on it but went backwards, we'll sort it for tomorrow."

Last year's British Superbike champion Neil Hodgson heads the provisional second row after taking fifth place with 1996 world champion Troy Corser sixth. Wild card rider Doug Chandler - Eric Bostrom's Kawasaki team-mate - finished the opening day's action in seventh place.

Suzuki rider Pier-Francesco Chili completes the provisional second row in eighth. Corser's Aprilia team-mate, Frenchman Regis Laconi, was ninth on his Laguna Seca debut. British Ducati privateer James Toseland completes the top 10, on his first visit to Laguna Seca since he rode a SuperSport machine there in 1999.

Australian Ducati privateer Steve Martin was 15th quickest.  Peter Goddard and the new Benelli 21st, Broc Parkes 23rd and Marty Craggill 26th.

1. Ben Bostrom, 1m25.248s
2. Eric Bostrom, 0.308s
3. Troy Bayliss, 0.827s
4. Colin Edwards, 0.864s
5. Neil Hodgson, 0.915s
6. Troy Corser, 0.987s
7. Doug Chandler, 1.039s
8. Pierfrancesco Chili, 1.290s
9. Regis Laconi, 1.357s
10. James Toseland, 1.364s
11. Stephane Chambon, 1.531s
12. Gregorio Lavilla, 1.737s
13. Tadayuki Okada, 1.783s
14. Ruben Xaus, 1.802s
15. Steve Martin, 1.886s
16. Lucio Pedercini, 1.944s
17. Akira Yanagawa, 2.124s
18. Robert Ulm, 2.167s
19. Giovanni Bussei, 2.189s
20. Marco Borciani, 2.259s
21. Peter Goddard, 2.302s
22. Michele Malatesta, 2.584s
23. Broc Parkes, 2.695s
24. Mauro Sanchini, 2.877s
25. Bertrand Stey, 3.159s
26. Marty Craggill, 3.888s
27. Jiri Mrkyvka, 5.044s
28. Javier Rodriguez, 5.539s
29. Ferdinando Di Maso, 6.480s