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A quartet of swimming finals took place on Monday night (Tuesday afternoon local time in Japan) at the Tokyo Aquatics Center, and only one American claimed gold. The big winner was 17-year-old Lydia Jacoby, Alaska's first ever Olympic swimmer. 

She earned that top honor in the women's 100-meter breaststroke. Defending Olympic champion and fellow American Lilly King took home bronze in that race.

American swimmers Regan Smith and Ryan Murphy also medaled, as both won bronze in their respective events.

Here's a race-by-race recap of Monday's swimming action: 

Women's 100-meter breaststroke

Jacoby stole the show. She swam well above her years by claiming America's lone swimming gold on the night. King came into the race as the favorite -- having won it at the 2016 Rio Games -- but Jacoby showed she could hang with her and the rest of the competition by finishing with the second-best semifinal time (1:05:52). 

Then, in the final, Jacoby clocked a time of 1:04.95, better than anyone else in the pool. Here's a look at the final stretch of the race:

And here is her hometown of Seward, Alaska -- which has population of around 2,600-- reacting to the win. Of note: in all of Alaska, there is only one 50-meter swimming pool. One! 

Men's 200-meter freestyle

Britain dominated the race, as Tom Dean (1:44.22) and Duncan Scott (1:44.26) finished 1-2 in impressive fashion. Dean's gold medal was Britain's first in the event since 1908. Brazil's Fernando Scheffer claimed bronze with a time of 1:44.66. American Kieran Smith, who came into the 200-meter final with high expectations after posting the second-best semifinal time (1:45:07), posted a disappointing 1:45.12 to finish sixth. 

Women's 100-meter backstroke

In the event's semifinal, Canadian Kylie Masse set a world record with a time of 58.17 -- only for American Regan Smith and Kaylee McKeown to break it just after. Those three swimmers continued their competitive rivalry in the final. McKeown (57.72) became the first Australian woman to earn gold in the event, with Masse (57.72) and Smith (58.05) earning silver and bronze, respectively. Smith's American counterpart, Rhyan Elizabeth-White, finished just behind her with a 58.43 to place fourth. 

Men's 100-meter backstroke

Russians Evgeny Ralnov and Kilment Kolesnikov claimed first and second in the event, respectively, leaving American Ryan Murphy with bronze. Murphy, who posted the event's best semifinal time (52:24), has now won consecutive bronzes after claiming one in the 400-meter freestyle earlier this week. 

A historic streak was broken in this race. It marked the first time since 1992 that an American man did not win. Team USA men had won the 100-meter backstroke and 200-meter backstroke in every Olympics dating back to 1996.