2019 2019 World Junior Championships When she was 15 years of age, Curzan competed at the
2019 World Junior Championships in
Budapest,
Hungary, winning a total of four medals, of which three were in individual events. On August 21, she won her first medal of the Championships, a silver medal in the 100 meter backstroke with a time of 1:00.00. She followed her silver medal up with a bronze medal on August 23 in the 50 meter butterfly, where she finished third in 25.81 seconds, just 0.11 seconds behind the gold medalist in the event and fellow American
Torri Huske. On the final day of competition, August 25, she finished third in the 100 meter butterfly with a time of 58.37, winning the bronze medal and missing out on the gold medal to Torri Huske. She wrapped up her competition swimming backstroke on the 4×100 meter medley relay, splitting a time of 1:00.75 and helping the relay win the
gold medal in a time of 3:59.13.
2020–2021 As a 16-year-old in August 2020, Curzan set a new
National Age Group record in the 100 yard butterfly for the girls 15–16 age group with a time of 49.73 seconds. In November, at the
2020 U.S. Open Swimming Championships, she won the gold medal in the 100 meter butterfly with a
Championships record of 56.61 seconds, the bronze medal in the 100 meter freestyle with a 54.93, and placed fourth in the 50 meter freestyle with a 25.23 and the 100 meter backstroke with a 1:00.30. At the 2021 TAC Titans Premier Meet, conducted in long course meters in April, she became the second-fastest female American performer ever in the 100 meter
butterfly, with a time of 56.20 seconds that moved her up in rankings behind fastest female American
Dana Vollmer and ahead of third-fastest female American
Kelsi Dahlia. The 56.20 was a girls 15–16 and 17–18 national age group record and a
world junior record. The following month, at the 2021 TAC Spring Invitational, she set a new world junior record in the long course 50 meter freestyle with a time of 24.17 seconds. Two days later at the invitational, she set a new girls 15–16 national age group record in the long course 100 meter freestyle with a personal best time of 53.55 seconds, breaking the former record of 53.63 seconds by
Missy Franklin in 2011.
2020 Olympic Trials In 2021, Curzan placed second in the final of the 100 meter butterfly at the
US Olympic Team Trials in
Omaha, Nebraska with a time of 56.43 seconds, qualifying her for the
2020 US Olympic Team. The 2020 Olympic Games were the first
Olympic Games she qualified to compete at, making her just 16 years old when she qualified and 17 years old at her Olympic debut.
2020 Summer Olympics At the
2020 Summer Olympics in
Tokyo, Japan and held in 2021 due to the
COVID-19 pandemic, Curzan placed tenth in the
100 meter butterfly and won a silver medal in the
4×100 meter medley relay for her contribution swimming the butterfly leg of the relay in the prelims. The silver medal she won for her efforts as part of the prelims relay consisting of herself,
Rhyan White (backstroke),
Lilly King (breaststroke), and
Erika Brown (freestyle) was her first
Olympic medal of any kind.
2021 World Short Course Championships Curzan was announced to the United States team for the
2021 World Short Course Championships in late October, with the announcement of the team earning the number two spot for "The Week That Was" honor from
Swimming World. Building up her
short course racing prowess in advance of the 2021 World Championships, she broke the national high school records, both overall and independent records for each event, in the 100 meter butterfly with a time of 57.08 seconds, in the 50 meter freestyle with a 24.94, and in the 100 meter backstroke where she set the new record at 58.40 seconds. Her three records captured the number three spot for "The Week That Was" honor for the week of November 22. Prior to the start of competition, Curzan entered to compete in three individual events, the 50 meter freestyle, 50 meter butterfly, and 100 meter butterfly. Commencing competition on day one, she swam in both the prelims and the final of the
4×100 meter freestyle relay, helping achieve a gold medal-win in the final with a time of 3:28.52, splitting a 52.25 for the second leg of the relay. In the morning of day two, she split a 24.87 for the butterfly leg of the
4×50 meter medley relay in the prelims heats, helping advance the relay to the final ranked first. She split a 24.56 for the same leg in the final, helping achieve a silver-medal-winning time of 1:43.61 with finals relay teammates Rhyan White,
Lydia Jacoby, and
Abbey Weitzeil. She qualified for the semifinals of the
50 meter butterfly in the morning prelims session on day three, ranking fourth with her time of 25.17 seconds. In the evening she qualified for the final of the 50 meter butterfly with a time of 25.20 seconds, which tied her with
Arina Surkova of
Russia and Torri Huske for fifth-rank heading into the final. For the final of the
4×50 meter mixed medley relay, she helped win the silver medal in a time of 1:37.04, swimming a 24.85 for the butterfly leg of the relay. In the final of the 50 meter butterfly on day four, Curzan won the bronze medal with a
world junior record,
Americas record, and
American record time of 24.55 seconds. In the prelims heats on day five, she ranked second in the
100 meter butterfly with a time of 56.46, less than half a second slower than first-ranked
Louise Hansson of
Sweden, and qualified for the semifinals in the evening. Later in the morning, she swam a 24.11 in the prelims of the
50 meter freestyle and qualified for the semifinals ranking eighth. Starting her competition in the evening, she tied the world junior record in the 100 meter butterfly with a time of 55.64 seconds in the semifinals and qualified for the final ranking second. Finishing her day five events, she qualified for the final of the 50 meter freestyle ranked sixth with a time of 23.80 seconds in the semifinals. For her first final on the sixth and final day of competition, Curzan won a gold medal in the
4×50 meter freestyle relay with a relay time of 1:34.22 and to which she contributed a split of 23.40 seconds for the second leg of the relay. In her second final, she won a bronze medal in the 100 meter butterfly with a world junior record-setting time of 55.39 seconds, which was less than four-tenths of a second slower than the 55.04 swam by gold medalist
Margaret MacNeil of
Canada. In her third final of the session, she placed sixth in the 50 meter freestyle behind fifth-place finisher and teammate Abbey Weitzeil with a 23.91. In her fourth of four finals for the day, she helped achieve a fourth-place finish in the
4×100 meter medley relay alongside finals relay teammates
Katharine Berkoff (backstroke),
Emily Escobedo (breaststroke), and Abbey Weitzeil (freestyle), splitting a 55.61 for the butterfly leg of the relay.
2022 In February 2022, Curzan set a new national high school record in the 100 yard backstroke with a time of 50.47 seconds, which was over four-tenths of a second faster than the previous record from 2020 by
Phoebe Bacon of 50.89 seconds. The next week, at the year's North Carolina High School State Championships, she set a new American record in the 100 yard butterfly with a time of 49.24 seconds and broke her national high school record in the 100 yard backstroke with a 49.61. At the
2022 US International Team Trials in April, she qualified for the
2022 World Aquatics Championships team in the 100 meter freestyle, 100 meter backstroke, 50 meter butterfly, and 100 meter butterfly.
2022 World Championships At the
2022 World Aquatics Championships, held at
Danube Arena in Budapest, Hungary, Curzan won her first medal of
competition in the
4×100 meter freestyle relay on day one, anchoring the relay with a 52.71 in the final to help win the bronze medal in 3:32.58. The next day, she placed fifth in the final of the
100 meter butterfly with a 56.74, which was over one second behind gold medalist Torri Huske. On June 20, day three, she won her first medal in an individual event, finishing third to win the bronze medal in the final of the
100 meter backstroke with a time of 58.67 seconds that was 1.10 seconds faster than the fourth-place finisher and 0.45 seconds slower than the first-place finisher. In the final of the
4×100 meter mixed medley relay the following day, she followed
Hunter Armstrong (backstroke),
Nic Fink (breaststroke), and Torri Huske (butterfly), with a 52.62 for the freestyle leg of the relay to help finish in a time of 3:38.79 and win the gold medal. Two days later, Curzan swam a 53.81 in the final of the
100 meter freestyle, finishing 1.14 seconds behind gold medalist
Mollie O'Callaghan of
Australia to place eighth. The finals session of the following day, she started off with a fifth-place finish in the
50 meter butterfly in a personal best time of 25.43 seconds. She concluded the evening session winning a bronze medal in the
4×100 meter mixed freestyle relay in a 3:21.09 achieved with finals relay teammates
Ryan Held,
Brooks Curry, and Torri Huske. She won her second gold medal and final medal of the Championships on the eighth and final day, anchoring the
4×100 meter medley relay to a first-place finish 0.47 seconds ahead of the second-place team from Australia in a final time of 3:53.78.
2022 World Short Course Championships On day one of the
2022 World Short Course Championships in December in
Melbourne, Australia, Curzan won a silver medal in the
4×100 meter freestyle relay, contributing a 51.59 to the final, and an Americas and American record, time of 3:26.29 for the third leg of the relay in the final. The second day, she won a bronze medal in the
100 meter backstroke with a personal best time of 55.74 seconds that tied
Ingrid Wilm of Canada. Later in the session, she tied for fifth-place with
Mélanie Henique of
France in the final of the
50 meter butterfly, finishing in a time of 24.92 seconds. Day three, she won her first gold medal of the Championships in the
4×50 meter freestyle relay, helping finish first in the final in a
Championships, Americas, and American record time of 1:33.89. Approximately 20 minutes later, she ranked twelfth in the semifinals of the
50 meter freestyle with a 24.22, 0.85 seconds behind first-ranked
Katarzyna Wasick of
Poland, and did not advance to the final. Day five, she started the evening session off with a silver medal in the
4×50 meter medley relay, where she swam a 25.75 for the backstroke portion of the relay to contribute to a final time of 1:42.41. She finished her evening competition for the day in the semifinals of the
100 meter butterfly, ranking fifth with a 56.37 before withdrawing from competing in the final. For her first of two finals on day six of six, Curzan won the silver medal in the
200 meter backstroke with a personal best time of 2:00.53, finishing 1.27 seconds behind gold medalist and world record holder in the event
Kaylee McKeown of Australia.
2023 2023 Pac-12 Championships Stating off the first collegiate championships season of her
NCAA career on the first day of the 2023
Pac-12 Conference Championships, held in February at the
King County Aquatic Center in
Federal Way, Washington, Curzan led-off with a 23.34 for the backstroke leg of the 4×50 yard medley relay, helping place second in 1:35.42. The following day she won her first conference title in the 4×50 yard freestyle relay, where she contributed a 21.59 to a final time of 1:25.98 for the lead-off leg of the relay. After a disqualification in the final of the 100 yard butterfly on day three, she rebounded to win the first individual event conference title of her collegiate career in the 100 yard backstroke, where she set a new Championships record with a time of 49.46, which lowered the mark 0.04 seconds from the previous record set by
Regan Smith one year earlier. The 49.46 also set a new girls 17–18 national age group record in the event. In her third event of the evening, she finished the backstroke leg of the 4×100 yard medley relay in 49.76 seconds to help win the conference title with a final mark of 3:25.79. For her first event on the final day, Curzan won the gold medal and conference title in the 200 yard backstroke with a Championships record of 1:47.43, which was 0.84 seconds faster than the former record of 1:48.27 by
Kathleen Baker in 2018. In her second of two events she won the conference title as well, this time anchoring with a 47.15 for the 4×100 yard freestyle relay to help finish first in 3:08.83. For the 4×50 yard freestyle relay the next day, she swam the second 50 yard portion of the relay in 20.98 seconds, contributing to a final time of 1:25.70 and a silver medal-win. In her first final on the evening of day three, she placed fourth in the 100 yard butterfly with a time 50.09 seconds. Concluding the day in her third final of the evening, for the 4×100 yard medley relay, she helped finish in 3:26.10 and place fourth. In her final event, she anchored the 4×100 yard freestyle relay to a silver medal-win in 3:08.54, splitting a 46.85. ==International championships==