KRASNAYA POLYANA, Russia -- Snowboarder Sage Kotsenburg thrives on the unexpected. He threw in a trick he’d never done before to win the first gold medal Saturday for Team USA at the Sochi 2014 Olympic Winter Games.

It was a day of firsts for the 20-year-old at Rosa Khutor Extreme Park.

Kotsenburg also won the first slopestyle competition held at the Winter Games. He was the first gold medalist of these Games in any event. He was the first to perform the “Holy Crail,” a grab he invented a couple of months ago. And he was the first U.S. athlete to win the first event of the Games since Andrea Mead Lawrence won the giant slalom in 1952.

“I just kind of do random stuff all the time,” said Kotsenburg, who was born in Idaho and grew up in Park City, Utah. “I never really make a plan up. I had no idea I was going to even do a 1620 in my run until three minutes before I dropped. That’s kind of what I’m all about.”

But he admitted, “I’m pretty surprised I won, honestly.”

The 1620 is four-and-a-half revolutions with a “Japan” air mute grab, which is behind the back. The judges rewarded Kotsenburg for his creativity with that move and his Holy Crail with a score of 93.50 points.

The score held up through the second run, with Staale Sandbech of Norway the only other rider to score in the 90s. His 91.75 gave him second place ahead of Canada’s Mark McMorris.

Canadian Max Parrot, the X Games champion, was fifth.

“I think all the riders were stoked today with how everything was organized,” Kotsenburg said. “We just went out there and rode. On a global level, it’s sick to have snowboarding in (the Olympic Winter Games). All of us were having a blast. You could see us all high-fiving at the bottom.”

He said riders were not “bummed” when someone else came down and landed a run. They wanted to see their friends do well. He’s known McMorris and Sandbech since they were kids.

“We’ve become such good friends and it’s sick to be on the podium with them, and everyone’s stoked for each other,” Kotsenburg said. “Snowboard’s one of the most friendly sports out there. Everyone is actually friends and homies. We all grew up together. We do the same sport. There’s not just competing with someone, there’s also filming. So you don’t want to burn bridges competing when you might be filming with them in the next couple of years.”

After Shaun White, the two-time reigning Olympic halfpipe champion, jammed his wrist and withdrew from the slopestyle event, U.S. hopes for a gold medal appeared to be on a slippery slope.

Kotsenburg, Ryan Stassel and Chas Guldemond advanced to the semifinals; however, only Kotsenburg emerged as a finalist. Stassel wound up 14th with a score of 83.25 from the semifinal, while Guldemond was 15th at 79.75 in the 29-man field.

Kotsenburg, who started snowboarding at age 5 with his older brother, Blaze, won a U.S. skiing regional event at age 11. He didn’t recall winning another competition until Jan. 18, when he took a U.S. Grand Prix victory at Mammoth Mountain, Calif., to punch his ticket to Sochi.

“I had a mega-drought there for a minute,” said Kotsenburg, who had plenty of seconds and thirds to make his reputation on the circuit. “To win (at Mammoth) and then I really blew it at X Games, and then coming here and winning, I can’t even describe the feeling. It’s so cool.”

He skipped Friday night’s Opening Ceremony to rest, watching the show while eating snacks and onion rings.

Kotsenburg came into Saturday just hoping to get through the semis. He had the second-best score in the round of 90.50 on his second run. Great Britain's Billy Morgan scored 90.75, though he eventually ended up 10th.

“Once I got to finals, I thought, ‘Alright, let it really rip,'” Kotsenburg said.

“The level of riding today was pretty crazy and seeing everyone ride and everyone’s doing triples and 1440s and 1620s today, it’s pretty unreal. But I think these guys could have won on any given day. It just ended up being my day today.”

He called his brother, who was watching with family and friends in Salt Lake City, before his run and told him he might try the 1620 Japan. “He was like, ‘Send it, what do you got to lose?’” Kotsenburg said. “I ended up landing it and winning it.”

He did have to talk himself up as he went into it: “It’s just another rotation, just whip it around at the end and you’ve got this.”

On his second run, Kotsenburg scored only 83.25. After riding third, he then had to wait through nine other riders to see if his first-run score would be enough.

Some observers thought McMorris, who was competing with a broken rib, had a superior run on his second try. “To ride the way I wanted to ride is the most important, the rest is up to the judges,” he said. “I’m happy with the outcome. A lot of people think it should have been different, but I’m going to still smile and represent Canada the best I can.”

Kotsenburg’s teammates from the men’s and women’s sides were in the finish area, chanting “U-S-A, U-S-A” when the final rider’s score came in under Kotsenburg’s.

“There's nothing like starting out the Olympics for Team USA with a gold medal,” said Mike Jankowski, U.S. Snowboarding halfpipe and slopestyle coach. “The momentum is something we look forward to all the teams grasping onto it to and really use it as energy to move forward themselves.”

Kotsenburg said he is inspired by old snowboard movies. When he saw the U.S. halfpipe team sweep at the 2002 Games in Salt Lake City, “I was kind of, ‘Whoa, snowboarding’s on a huge global level,’” he said. “There’s no blueprint to snowboarding. You can really make your own mark and put your own flair on tricks.”

And pull off some firsts.