2025 World Junior Swimming Championships
- August 19-24, 2025
- Otopeni, Romania
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GIRLS’ 100 BUTTERFLY – Semifinals
- World Record: 54.60 – Gretchen Walsh, United States (2025)
- World Junior Record: 56.33 – Mizuki Hirai, Japan (2024)
Championship Record: 57.25 – Rikako Ikee, Japan (2017)
Final Qualifiers:
- Mizuki Hirai (Japan) — 57.02 *Championship Record*
- Audrey Derivaux (United States) — 57.57
- Gong Zhenqi (China) — 57.84
- Charlotte Crush (United States) — 58.17
- Clare Watson (Canada) — 58.60
- Serafima Fokina (NAB) — 58.77
- Aliisa Soini (Finland) — 58.93
- Caterina Santambogio (Italy) — 58.96
Mizuki Hirai stunned in the semifinal of the girls’ 100 fly tonight in Otopeni, throwing down a time of 57.02 to break the Championship Record.
The Japanese swimmer improved upon her time from prelims (57.41) and shaved .23 off of the record time, which previously stood at 57.25. The former Championship Record was set by Rikako Ikee, also of Japan, back in 2017.
Hirai holds the World Junior Record in the girls’ 100 fly at 56.33, which she broke back in June 2024 at a high school meet in Japan. While her swim tonight was not a personal best, Hirai delivered a strong performance to take down the meet record in the semifinal of the event, boasting the fastest splits across the board.
She was out fast in 26.65, gaining an early lead before coming home in 30.37. Hirai heads into the final seeded .55 ahead of American Audrey Derivaux, who posted a best time of 57.57 to snag the runner-up spot.
Splits Comparison
| Hirai – New CR | Ikee – Old CR | Hirai – WJR | |
| 50 | 26.65 | 27.14 | 26.26 |
| 100 | 57.02 (30.37) | 57.25 (30.11) | 56.33 (30.07) |
With another race ahead of her in the 100 fly, Hirai certainly has room to improve upon her time and the Championship Record even further, though she will face tough competition from Derivaux.
Hirai has already posted a series of top performances at the World Junior Championships this week. She picked up a gold medal as part of Japan’s winning mixed 4×100 medley relay (3:45.57), won silver in the girls’ 50 fly (25.66) and placed 7th in the girls’ 100 free (55.01).
Unofficial summation of points from today’s session events. Points for Places 1 – 8 from today’s finals, plus points for 9 – 16 from semi’s or prelims of the same events.
NAB takes 20 point lead for Championship Trophy, with one scoring session remaining.
Women’s 1500
NAB 16, 12 = 28
USA 14, 11 = 25
Men’s 50 Fly
NAB 13, 8 = 21
USA 0, 0 = 0
Women’s 50 Back
NAB 13, 0 = 13
USA 10, 1 = 11
Men’s 400 IM
NAB 11, 10 = 21
USA 14, 4 = 18
Women’s 4×100 FR
NAB 32
USA 36
Totals this session:
… Read more »
How a bout an article touching on what may be the biggest story of the meet.
USA usually wins medal table, though not necessarily GOLD medal table, and the POINTS championships (“CHAMPIONSHIP Trophy”) in major international swimming events. This perpetually drives countries with a slew of Gold medalists (often Australians), but not as much depth, crazy. It’s usually not even close.
This time it is close. Not with Australia but with Neutral Athletes – B (fake name for Russia arising out of response to the Russian attack on Ukraine).
From the World Aquatics Omega Timing site:
Championships Trophy
After 31 of 42
Events Rank NAT NAT Code Men Women Mixed Total
1 United States of America… Read more »