Austria's David Gleirsche took home the gold, while Germany's Johannes Ludwig earned bronze.
Halfway through the four-round event, Mazdzer was in fourth place, with a total time of 1:35.517 - just one one-thousandth of a second behind Roman Repilov, Olympic Athlete from Russian Federation, but it would have been enough to keep him off the medal stand.
Tucker West of Ridgefield, who was competing in his second Olympic Games in luge, finished a disappointing 26 in the Winter Games in Pyeongchang Sunday.
Saranac Lake's Chris Mazdzer is the first American man ever to medal in men's luge singles.
Team USA is starting to gain momentum in the medal hunt at the 2018 Winter Olympics. In both 2010 and 2014, he finished 13th.
It's no surprise, Mazdzer's second run was the fastest in that heat demonstrating he was capable of medaling.
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"It's a massive honour to overtake Matt, who was a hero of mine growing up", said Leeds-born Care. I'll have to have a chat with uncle Eddie after the game.
Gleirscher's cumulative time over four runs (Runs 1 and 2 took place on Saturday, with Runs 3 and 4 on Sunday) was 3:10.702, as he won by 0.026 over Mazdzer.
He was all set to create history ahead of his final run, as his medal rivals promised little.
Mazdzer finished 13th in two previous Winter Games, so this was quite a step up.
Loch, who seemed a lock to win his third straight gold medal, hit a wall on his final run and fell to fifth place in the final standings.
The highest the US men had ever placed in the Olympics was fourth in 2002 (Adam Heidt) and 2006 (Tony Benshoof).
Fans of Chris Mazdzer, including his girlfriend Mara Marian (C), react following his third run during the luge men's singles at the Olympic WInter Games PyeongChnag 2018 on February 11, 2018 in PyeongChang, South Korea.
On the fourth and final run, Loch did what he had never done before in the Olympic Games - he had a disastrous run.