Mazdzer, a three-time Olympian who finished 13 at the last Olympics, wore his lucky No. 13 and was in fifth place after his first run and fourth after his second run, when he set a track record of 47.534 seconds.
Hey, it took just 54 years.
Chris Mazdzer slides during the men's singles luge at the Olympic Winter Games PyeongChang 2018 on February 11, 2018 in PyeongChang, South Korea. Loch had appeared well on his way to earning his third Olympic gold medal in a row - but a disastrous final run unraveled his bid for a three-peat, knocking him not only out of the top spot but also off the podium entirely.
Mazdzer had a little trouble in run 4, but held it together and it looked like he would end up with a bronze medal.
David Gleirscher of Austria took gold and Johannes Ludwig of Germany took home bronze.
NPR's Melissa Block reports he leaped from his sled after that final run, vaulting "into the stands to hug his family and grab an American flag".
Mazdzer won silver in the men's singles luge - becoming the first American to medal in the event.
The 29-year-old from Saranac Lake, New York, headed into Sunday's final two runs just one thousandth of a second out of third and two tenths of a second off the leader, two-time gold medalist Felix Loch of Germany.
Mazdzer had slumped on the World Cup circuit recently, but it didn't matter on the world's biggest stage.
Before Sunday, the highest an American had finished in the singles luge was fourth place.
The highest the USA men had ever placed in the Olympics was fourth in 2002 (Adam Heidt) and 2006 (Tony Benshoof).
The U.S. had already medaled in women's singles luge - Erin Hamlin was the first to do so, winning bronze in 2014 - as well as doubles luge.