The United States has a new swimming star after Lydia Jacoby scored a stunning upset in the women's 100-meter breaststroke to win the gold medal at the Tokyo Aquatics Centre on Tuesday. The 17-year-old swam the race of her life to give Team USA its third gold medal in the swimming competitions in the Tokyo Olympics.

Nobody considered Jacoby to be a gold medal contender heading into Tuesday's finals, given the strength of her opponents, particularly American compatriot Lilly King and South Africa's Tatjana Schoenmaker. King is the reigning Olympic champion in this event, while Schoenmaker just set the Olympic record in the semifinal.

Jacoby outlasts Schoenmaker and King in thrilling finish

However, Jacoby prevailed in the end, finishing the race with a time of 1:04.95. Schoenmaker grabbed the silver medal, trailing Jacoby by 0.27 seconds. King rounded out the podium places, finishing in third place with a time of 1:05.54.

It was a disappointing end to King's reign, who was widely tipped to repeat as Olympic champion here. It certainly looked that way at the start as King led most of the way through the first 50 meters of the race. Schoenmaker, however, managed to grab the lead at the turn, moving 0.30 seconds ahead of King heading into the final 50 meters of the race.

As the race between King and Schoenmaker heated up, Jacoby held firm in third place. She then surprisingly surged into first place during the final 15 meters, with King and Schoenmaker close behind. To everyone's surprise, including Jacoby, it was the 17-year-old who pulled off the win, recording one of the major upsets in recent swimming history.

Jacoby made history with her victory as she became the first Alaskan to win a gold medal in the Olympics. Jacoby's road to the Olympics has been anything but easy. Before the Tokyo Games, Jacoby had never competed in a major international event.

From nobody to Olympic champion

No one gave her a shot when the U.S. Olympic Trials came around as she was seeded 15th overall in the event. Jacoby persevered though and managed to qualify for the team by posting a personal-best time of 1:05.28.

The Cinderella story continued in Tokyo as Jacoby handed her teammate, King, her first loss in this event since 2015. Not bad for a swimmer who, until last month, never had access to an Olympic-length swimming pool.

Apart from Jacoby and King, two other Americans grabbed medals on Day 3 of the swimming competitions. Regan Smith captured the bronze medal in the women's 100-meter backstroke event with a time of 58.05 seconds. On the other hand, Ryan Murphy won the bronze medal in the men's 100-meter backstroke event, finishing with a time of 52.19 seconds.

Murphy was looking to win back-to-back gold medals in this event but was thwarted by ROC swimmers Evgeny Rylov (51.98 seconds) and Kliment Kolesnikov (52 seconds), who won gold and silver, respectively.

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