Editor's note: This article originally appeared at Competitor.com.

Ending weeks of speculation, reigning Olympic 10,000-meter silver medalist Galen Rupp announced Thursday that he’ll be making his marathon debut at the U.S. Olympic trials on Feb. 13 in Los Angeles.

Rupp qualified for the race on Dec. 13, winning the Foot Traffic Holiday Half Marathon in Portland, Ore., in 1 hour, 1 minute, 20 seconds -- well under the U.S. Olympic trials "B" standard of 1:05:00.

"I’m really happy and excited to announce that I’ll be running the Olympic Trials coming up in February, in the marathon," Rupp said in an exclusive announcement on USATF.TV.

The 29-year-old Rupp, who trains as a member of Alberto Salazar’s Nike Oregon Project, said that the 10,00 meters will still be his primary focus for 2016. He’ll attempt to make the Olympic team in the marathon in an effort to give him more flexibility in regard to which events he’d like to race at this summer’s Games in Rio.

"The 10K is still my primary focus but I’m excited about the possibility of doing that and the marathon or that and the 5K," said Rupp, who also ran the 5,000 meters for the U.S. in London, where he finished seventh.

Rupp, who finished fifth in both the 10,000 and 5,000 at last summer’s world championships, has captured seven straight national titles in the 10,000 and holds the American record of 26:44.36 in the event. In the 5,000, Rupp has won one national title and is one of only a handful of Americans to have broken 13 minutes (12:58.90) for the 12.5-lap race.

At global championships since 2009, he has finished eighth or better five times in the 10,000, while in the 5,000 he has four top-10 finishes to his name.

Salazar, the former three-time New York City Marathon champion and Boston Marathon champion who has coached Rupp since he was 16 years old, brought up the idea of the marathon out of the blue after the disappointment of last year’s world championships in Beijing.

"After this last summer it kind of came up in conversation with Alberto,” explained Rupp, whose 60:30 half-marathon personal best is the fifth-fastest U.S. time in history. "He just said to keep an open mind with it. We’re not going to commit to anything ... it took me a little while to wrap my head around it.

"It’s definitely a new challenge and it’s a little daunting just because I’ve never done it before. It’s such a big step up in distance but I’m really excited to give it a shot and I think with everything we’ve done to prepare me that it’s going to turn out alright."

Rupp will face a formidable field in L.A., including defending trials champion and 2014 Boston Marathon winner Meb Keflezighi, four-time Olympian Abdi Abdirahman, Dathan Ritzenhein (Rupp’s former Oregon Project training partner and top American finisher in Boston in 2014), and reigning U.S. marathon champion Jared Ward, among others.

Ryan Hall, the Olympic trials marathon record-holder (2:09:02) who made the previous two Olympic teams in the marathon, announced his retirement earlier this month.

"It’s always tough in an Olympic year," said Rupp, who still plans to run the world indoor championships March 18-20 in Portland. "It’s way harder than a normal year because everybody ups their game and they definitely want to make the Olympic team, too. There’s obviously going to be a lot of challenges.

"There’s some great athletes in the field, guys that certainly have a lot more experience than I do in running a marathon. I know it’s going to be tough and I always say I have to respect the distance, respect the competition because it’s not going to be easy. Those guys have been so great for so long and they’re there for a reason and they’re definitely going to make it tough."