2025 World Championships
- July 27 – August 3, 2025 (pool swimming)
- Singapore, Singapore
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The reigning Olympic champion in the men’s 200 backstroke will have a shot at securing the world title in the 100-meter event tomorrow night after an impressive semi-final swim.
Hungary’s Hubert Kos rocketed down the second length during the second semi of the men’s 100 back, touching first in a time of 52.21 to chip three one-hundredths off his own National Record of 52.24 set in April at the Hungarian National Championships.
The 22-year-old now ranks 15th all-time in the event—he previously sat in a tie for 15th with Japan’s Ryosuke Irie at 52.24, but now holds sole possession of that spot.
Split Comparison
| 2025 Hungarian Nationals | 2025 World Championships |
| 25.07 | 25.30 |
| 52.24 (27.17) | 52.21 (26.91) |
Prior to clocking 52.24 three months ago, Kos’ best time stood at 52.78 from the 2024 Olympic Games. In Paris, after leading the prelims with that lifetime best time, Kos failed to earn a lane in the final, placing 10th overall in 52.98.
At the 2025 Men’s NCAA Championships in late March, Kos won the 100 back title in a time of 43.20 (short course yards), breaking the U.S. Open and NCAA Record after he was nearly a full second slower (44.13) at the same meet the year prior, showing how much his speed has developed since moving to the University of Texas just over one year ago.
Heading into tomorrow’s final of the 100 back, Kos leads a tightly bunched field that features eight swimmers separated by just 36 one-hundredths of a second.
Russia’s Kliment Kolesnikov sits 2nd in 52.26, followed by South African Pieter Coetze (52.29) and world record holder and reigning Olympic champion Thomas Ceccon (52.35).
