Lydia Jacoby took home the gold in the 100-meter breaststroke in a surprise win against teammate, returning champion and world-record holder Lilly King.
For the 17-year-old Jacoby, the win was not only her first ever gold medal, but also the first one in swimming for her home state of Alaska. Jacoby is the first person from the state to make it to the U.S. Olympic swim team.
"I was definitely racing for a medal. I knew I had it in me," Jacoby said after her win. "I wasn't really expecting a gold medal, so when I looked up and saw the scoreboard it was insane."
South African swimmer Tatjana Schoenmaker clocked in after Jacoby to win the silver, followed by King, who won the bronze.
"We love to keep that gold in the USA family," King said of her teammate's win. "This kid just had the swim of her life and I'm so proud to be her teammate and win bronze for my country."
Jacoby's win was celebrated with enthusiasm in her hometown of Seward, Alaska, where footage showed classmates and friends jumping and screaming as she closed in on victory.
Commentators from NBC noted that Jacoby trains in a 25-meter pool, rather than the Olympic sized 50 meters. There's only one known 50-meter pool in the entire state of Alaska and it wasn't close enough to her hometown.
Jacoby has committed to attending the University of Texas at Austin once she completes her last year of high school.