Team USA remained at the second spot after Day 4 of the Tokyo Olympics after adding two gold medals, five silvers and five bronzes to its medal tally.

Host nation Japan still holds the lead, with the Asian powerhouse already amassing ten gold medals, while erstwhile leader, People's Republic of China, tied with Team USA as the two countries have nine gold medals apiece after Day 4 of the ongoing Summer Games.

Lydia Jacoby wins gold for Team USA in a major upset

The states of Alaska and Hawaii provided Team USA with the gold medals on Day 4 after Lydia Jacoby and Carissa Moore recorded spectacular victories in their respective events. Jacoby swam the race of her life Tuesday in the women's 100-meter breaststroke to win the gold for Team USA.

The 17-year-old outlasted more heralded opponents, the likes of defending champion Lilly King and South Africa's Tatjana Schoenmaker, to become the first athlete from Alaska who has clinched a medal for Team USA in the history of the Olympics. It was a stunning victory for Jacoby, given that her compatriot King had not lost in this event since 2015.

That proved to be USA Swimming's only gold on Day 4 as Rio Olympics champion Ryan Murphy finished a disappointing third place in the men's 100-meter backstroke behind two ROC swimmers.

Carissa Moore makes history with first Olympic surfing gold

Hawaiian surfer Carissa Moore took home the other gold for Team USA in surfing, which just made its debut in this year's Tokyo Olympics. Moore captured the gold in the women's shortboard event, finishing ahead of South Africa's Bianca Buitendag, who won silver, and Japan's Amuro Tsuzuki, who won the bronze.

The 28-year-old Honolulu native entered the event as one of the favorites, and Moore duly delivered, breaking down in tears once she secured the gold medal for Team USA. Moore stamped her class against the opposition, beating Silvana Lima in the quarterfinals by a score of 14.26-8.30. Moore then defeated Tsuzuki, 8.33-7.43, in the semifinals before outclassing Buitendag in the finals, 14.93-8.46.

Moore has now added an Olympic gold medal to her long list of accolades. Moore, who began surfing at the age of 5, became the youngest world surfing champion at 18 and had a total of four world titles in her collection.

Jacoby and Moore were the only golden girls for Team USA on Day 4 as the Americans suffered heartbreaking losses in the women's gymnastics and women's softball events. Team USA failed to recover from Simone Biles' sudden withdrawal, losing to ROC in the women's gymnastics team finals.

On the other hand, Team USA women's softball suffered yet another painful defeat to Japan in the gold medal match, losing 2-0 in a rematch of their finals clash 13 years ago, which the Japanese also won.

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