2025 World Championships
- July 27 – August 3, 2025 (pool swimming)
- Singapore, Singapore
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Men’s 800 Freestyle — Prelims
- World Record: 7:32.12 — Zhang Lin, China (2009)
- World Junior Record: 7:43.37 — Lorenzo Galossi, Italy (2022)
- World Championships Record: 7:32.12 – Zhang Lin, China (2009)
- 2023 World Champion: 7:37.00 — Ahmed Hafnaoui, Tunisia
- 2024 Olympic Champion: 7:38.19 — Daniel Wiffen, Ireland
Top 8 Qualifiers:
- Ahmed Jaouadi (TUN) – 7:41.58
- Sam Short (AUS) – 7:42.22
- Sven Schwarz (GER) – 7:43.60
- Bobby Finke (USA) – 7:44.02
- Victor Johansson (SWE) – 7:44.81
- Kuzey Tuncelli (TUR) – 7:45.13
- Lukas Märtens (GER) – 7:45.54
- Daniel Wiffen (IRL) – 7:46.36
During the final event of the third preliminary session at the 2025 World Championships, 17-year-old Turkish rising star Kuzey Tuncelli clocked 7:45.13 in the men’s 800 freestyle, breaking his own national record.
Tuncelli set the previous mark of 7:46.01 earlier this month at the European Junior Championships, where he swept the 800 and 1500 (14:45.05) and also picked up bronze in the 400 free with a personal best of 3:49.50.
This morning, Tuncelli sat fourth for much of the race, but mounted a strong back-half charge. He overtook reigning Olympic champion Daniel Wiffen at the 500-meter mark to move into third, then passed 400 free world champion Lukas Märtens on the final 50. However, Sweden’s Victor Johansson surged in the closing 25 meters, leaving Tuncelli third in the heat and sixth overall heading into Wednesday’s final.
The heat was won by Tunisia’s Ahmed Jaouadi, last summer’s Olympic fourth-place finisher, who posted a lifetime best of 7:41.58 to lead all qualifiers.
Wiffen faded to fifth in the heat, while Sam Short, Sven Schwarz, and Bobby Finke went 1-2-3 in the next heat to secure their spots in the championship final.
Compared to his previous record, Tuncelli’s improvement came largely from the front half of the race. He turned 1.52 seconds ahead of pace at the 400 and ultimately lowered the mark by 0.88 seconds.
See a full splits comparison of Tuncelli’s two record swims below.
Splits Comparison:
| Tuncelli’s New National Record | Tuncelli’s Previous National Record | |
| 50m | 26.77 | 27.05 |
| 100m | 55.34 (28.57) | 55.80 (28.75) |
| 150m | 1:24.56 (29.22) | 1:25.01 (29.21) |
| 200m | 1:53.44 (28.88) | 1:54.34 (29.33) |
| 250m | 2:22.76 (29.32) | 2:23.64 (29.30) |
| 300m | 2:51.73 (28.97) | 2:53.01 (29.37) |
| 350m | 3:21.08 (29.35) | 3:22.39 (29.38) |
| 400m | 3:50.16 (29.08) | 3:51.68 (29.29) |
| 450m | 4:19.84 (29.68) | 4:20.86 (29.18) |
| 500m | 4:48.94 (29.10) | 4:50.35 (29.49) |
| 550m | 5:18.49 (29.55) | 5:19.80 (29.45) |
| 600m | 5:47.38 (28.89) | 5:49.29 (29.49) |
| 650m | 6:17.32 (29.94) | 6:18.70 (29.41) |
| 700m | 6:47.06 (29.74) | 6:48.26 (29.56) |
| 750m | 7:16.75 (29.69) | 7:17.84 (29.58) |
| 800m | 7:45.13 (28.38) | 7:46.01 (28.17) |
Tuncelli announced himself in 2023, becoming the youngest swimmer to crack the 15-minute barrier in the 1500 free and earning double gold in the distance events at the 2023 World Junior Championships. He continued improving in 2024, taking the next step in his career on the senior international stage which earned him the 2024 Swammy for World Junior Male Swimmer of the Year.
In 2024, Tuncelli won his first senior European Championship title, finishing first in the 1500 free with a time of 14:55.64. He went to the European Junior Championships a few weeks later and claimed double gold in the 800 and 1500 free. In the latter, he broke the world junior record, European junior, and championship record in 14:41.89. The swim knocked more than 12 seconds off his Turkey record and lifetime best of 14:54.16 as he moved to 18th all-time in the event and 8th among Europeans ahead of his 17th birthday.
The Paris Games were Tuncelli’s Olympic debut. In his first swim, he broke the Turkish record, clocking 7:47.29 for an 11th-place finish. He made the 1500 free final, where he chopped even more time off his world junior and national records, clocking a 14:41.22 to take fifth. The time improved his standing as the 18th fastest all-time in the event.
Tuncelli wasn’t done breaking records after the Olympic Games. He took over the official 1500 free world junior record at the 2024 Short Course Worlds, swimming 14:20.64 and winning bronze for his first medal at the senior World Championship level. He now owns the 1500 free world junior record in long-course and short-course meters. Tuncelli broke two Turkish records during the swim as his 800 free split of 7:38.76 broke his own national mark.
