Ryan Dungey (28) led much of the main event, battling with Broc Hepler (60) and Weimer on his way to second. Hepler was fourth. (Photo: Steve Cox) » More Photos

"I'm sure it will sink in tomorrow or something," Weimer said, "but right now, it's pretty hard to believe."

Dungey hung on for second and extended his points lead in the West to nine over Lawrence, who wound up fifth on the night. Metcalfe finished third, just in front of Hepler and Brayton.

Rockstar/Makita Suzuki's holeshot artist Mike Alessi lived up to his reputation in the 450cc main event, grabbing the holeshot just in front of defending champ James Stewart of the Monster Kawasaki squad and San Manuel Yamaha's Chad Reed, who won the opening round.

Stewart quickly assumed the lead, with Reed right on his tail, and the two proceeded to put on a clinic, as they lapped consistently in the 46-second range, while everyone else was running laps of 47 seconds and higher. Stewart even got into the 45s on a couple laps during the main event.

For the first few laps of the main, Reed was all over Stewart and was threatening to pass, but as the time wore on, Reed slipped little by little and fell further and further behind. Stewart ended up winning his first main event of the year by just under two seconds over Reed, with Torco Racing Fuels Honda's Kevin Windham, and Honda Red Bull Racing teammates Andrew Short and Ivan Tedesco rounding out the top five.

Reed and Stewart are tied atop the championship leaderboard each with 47 points with 15 rounds left still to run. The series heads back to Anaheim in one week's time for Anaheim II.