Ryan Villopoto won his very first 450cc AMA Motocross national at Glen Helen on Sunday.
The multiple Lites class champion picked up where he had finished his rookie Supercross-class season in Las Vegas, by winning both motos for Kawasaki.
The fast starting Mike Alessi, who provided the closest opposition for James Stewart last season, put his Makita Suzuki into second overall with 3-2 race finishes while Josh Grant completed the podium.
Chad Reed, who signed a late deal to race Outdoors after narrowly losing the Supercross title to Stewart, was fourth overall with a best race finish of third in moto two.
Stewart, who won every outdoor race last season, is not defending his crown, but is tipped to make a motocross grand prix appearance before the end of the 2009 season.
In the AMA Lites class, extra attention was on the debut of world championship stars Christophe Pourcel (2006 MX2 world champion), Tyla Rattray (2008 MX2 world champion) and Tommy Searle (2008 MX2 runner-up).
However, it was home grown star Ryan Dungey who claimed first blood with 2-1 moto finishes, handing the Makita Suzuki rider the overall victory by eight points over fellow 2009 AMA Lites Supercross champion Pourcel.
"I think overall it was a good day,” said Dungey. “We had solid practices and finished fastest in both. I ended up second in the first moto, had a little bobble in a corner, and kind of lost the lead. Going into the second moto, I didn't have such a great start but I worked my way through the pack and was able to get up to first. Two-one today for the overall? I think it was solid."
Pro Circuit Kawasaki rider Pourcel took victory in moto one, but was less successful in moto two, while third on the podium went to team-mate Rattray. The South African clocked 4-2 race results to edge out Searle by two points.
"Without racing for seven months I knew it would still take me a while to get used to racing again," said Rattray. "Before the first race I was a bit nervous, I didn't ride very good and rode too tight but I'm happy with the second moto. I got a good start and it was fun to be racing up front with Dungey. The track was very rough and the spectators really got into it so it was just a great experience for me and a good start to the USA series."
Searle was fourth in both races for KTM, beating Austin Stroupe by half a wheel in race two.