2025 World Championships
- July 27 – August 3, 2025 (pool swimming)
- Singapore, Singapore
- World Aquatics Championships Arena
- LCM (50m)
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The upsets continue to come in Singapore, as several notable names did not advance to the semifinals of the men’s 100 butterfly.
Team USA’s Shaine Casas and Thomas Heilman and the Netherlands’ Nyls Korstanje all failed to make it out of the preliminary heats of the event this morning, despite coming into the meet as some of the top-ranked swimmers in the world this season.
Casas placed 19th overall in 51.66, followed by Korstanje in 20th (51.67) and Heilman in 26th (52.02). It took a 51.58 to make it to semifinals, putting both Casas and Korstanje less than .1 outside of the cutoff.
Coming into the World Championships, the three swimmers had all looked liked strong contenders to make the semifinals and possibly the final. Casas was the #5 seed in the event, Korstanje was the #7 seed and Heilman was the #9 seed.
Casas is currently ranked 5th in the world this season, having posted a 50.51 at the U.S. National Championships in June. Just last night, Casas won silver in the 200 IM with a 1:54.30 behind France’s Leon Marchand.
Last summer, Korstanje placed 6th in the 100 fly in 50.83 at the Paris Games. His top time this season was a 50.97 from April, which ranked him 12th in the world leading up to the World Championships. Korstanje already raced the 50 fly in Singapore, tying for 6th in 22.84 alongside Luca Armbruster of Germany.
Meanwhile, Heilman finished 18th in this event in Paris with a 51.82, only to turn in a best time of 50.70 a year later at U.S. Nationals. Coming into these championships, Heilman was ranked 8th in the world this season. This was Heilman’s only individual event in Singapore.
This morning’s results brought Heilman and Korstanje’s individual campaign to a close; Casas is scheduled to race the 50 back on Saturday.
Shaine used all his power yesterday with that 1:54:30. Mess.
Both Milak WJRs survived Heilman then. Did not expect that after Fukuoka.
Heilman also had acute gastroenteritis
Has it ever happened that USA didn’t have a swimmer in both 100 back and fly semis?
Today
Why couldn’t Dare have made the team 😭😭😭
Because he was too slow.
It’s Greg Meehan’s fault Shane Casas is unpredictable and misjudged the prelims.
Mess
Casas opened and closed his redemption arc in less than 16h ☠️
Meh he still redeemed himself big time. It would be hard to get on the podium anyways with Grousset, Liendo, Ponti, and Kharun
He has 200 IM silver. He’s fine.
True and a pr by a second when it actually mattered in finals! Haven’t seen much of that from him so very glad to see it now