Ken Roczen wins main event at supercross opening race

Ryan Villopoto, the champion of supercross for the last four years, was back aboard his Kawasaki motorcycle at the sport’s season opener Saturday night at Angel Stadium.

But Villopoto’s single lap was only ceremonial, because he plans to race overseas this year. And after Villopoto climbed off his bike, his would-be title successors took to the Anaheim dirt.

Suzuki rider Ken Roczen then won the 20-lap main event in front of a sold-out crowd of 45,050 on Saturday night to grab the early lead in this year’s Monster Energy AMA Supercross Series championship battle.

Jason Anderson finished second, and Trey Canard was third.

Supercross is the stadium version of off-road motorcycle racing, or motocross, and Angel Stadium is the sport’s traditional opening venue. Supercross will return to Anaheim on Jan. 17 and 31 as part of its 17-race schedule.

With Villopoto gone, the sport will crown a different champion for the first time since 2010, when Ryan Dungey won his only title.

Dungey finished fourth Saturday night. Davi Millsaps of Murrieta, Villopoto’s replacement on his Kawasaki team, finished 19th after missing the 2014 season because of a knee injury.

James Stewart, another former champion, also was not in the field Saturday night.

Stewart recently was suspended until Aug. 11 after failing a drug test last spring that revealed amphetamines in his system. But Stewart, 29, said it was due to prescription medicine and he planned to appeal.

Stewart attended the Anaheim event, dubbed A1, as a spectator, signed autographs and wrote on Twitter: “This is why I love you guys. Mad support from the fans here at A1. I’ll be BACK!!!!”

In the sport’s second-level 250SX series, KTM rider Jessy Nelson of Paso Robles won the 15-lap main event with a 6.5-second cushion over second-place Zach Osborne.

james.peltz@latimes.com

Twitter: @PeltzLATimes