The highly anticipated 2013 Lucas Oil Pro Motocross Championship, sanctioned by AMA Pro Racing, kicked off last Saturday in sunny California, where the race action lived up to the off-season hype.

This Saturday, 25 May, the series moves into Lakewood, Colorado’s mile high altitude for the Rockwell Watches Thunder Valley National, round two of the 12-race series, at Thunder Valley MX Park.

Monster Energy Kawasaki’s Ryan Villopoto leads the highly competitive 450 Class into the second round this weekend after sweeping both motos of the Red Bull Hangtown Motocross Classic season opener.

After missing the entire 2012 season with injury, the 2011 champion made his return to the Lucas Oil Pro Motocross Championship with a dominant victory in his first race back.

Defending Lucas Oil Pro Motocross champion Ryan Dungey began his season with a pair of second place finishes at Hangtown, where the Red Bull KTM rider was in contention for the lead all afternoon.

As the 2012 Thunder Valley National winner, Dungey will head into the weekend with a strong desire to reclaim the top position in the championship point standings.

Yoshimura Suzuki’s James Stewart came out swinging this season after being absent for over half of last year’s championship. Stewart grabbed both Motorcycle-Superstore.com holeshots at round one, where a consistent (3-3) score awarded him a podium finish at Hangtown.

Stewart battled with Dungey and Villopoto over the course of the two motos, as the trio put on an exciting show that is sure to continue throughout the 2013 season.

Both Dungey and Stewart have had great success at the Thunder Valley National, combining previous wins to claim over half of the total 450 Class wins in the track’s history. Dungey currently holds the last three overall wins in Colorado, while Stewart claims the 2007 and 2008 victories.

However, some of the most exciting racing action at the season opener took place just beyond the podium positions. Team Honda Muscle Milk’s Trey Canard and Justin Barcia put in their all at round one, where the duo secured the fourth- and fifth-place positions respectively.

Other front-runners to keep an eye on include Smartop/MotoConcepts Mike Alessi, Joe Gibbs Racing Yamaha’s Josh Grant, Rockstar Energy Racing’s Ryan Sipes, Lucas Oil Troy Lee Honda’s Malcolm Stewart and Monster Energy/Pro Circuit/Kawasaki’s Dean Wilson.

Australia’s Chad Reed was 15th after battling illness, while countryman Michael Byrne was 19th in his competitive return.

Ken Roczen, the 2011 MX2 World Champion, opened the season in a big way, securing his first career 250 Class victory at the Red Bull Hangtown Motocross Classic.

The Red Bull KTM rider battled with teammate Marvin Musquin, Eli Tomac and defending 250 Class champion Blake Baggett, but Roczen proved to be the dominant force with a (1-1) sweep.

GEICO Honda’s Tomac also put himself into contention for the lead in both motos, trading lead positions with Baggett, Musquin and even teammate Zach Osborne early on.

Tied with Baggett for second place in the current standings, Tomac heads into his home state of Colorado this weekend with an even bigger desire to take over the number one spot.

Last season at Thunder Valley in the 250 Class, Justin Barcia emerged victorious with (1-2) moto scores.

Barcia’s full-time move to the 450 Class this season leaves 2011 Thunder Valley champion Blake Baggett as the only past winner to remain in the division, increasing the chances of a potential first-time event winner in Colorado.

Since becoming part of the Lucas Oil Pro Motocross Championship in 2005, Thunder Valley MX Park has grown to be one of the series’ most popular stops.

With its mile-high elevation and sprawling layout, Thunder Valley presents one of the most unique challenges for both the riders and their teams. The thin mountain air robs bikes of power while also testing a rider’s endurance.

It is a one-of-a-kind combination that is only found at Thunder Valley and each year, it is one of the race’s most prominent storylines. Additionally, its picturesque setting and hillside location make it one of the best venues for fans, with incredible sight lines from any point on the track.

The races will be aired live on Speed TV Australia at 7:00am AEST on Sunday, 26 May.