2025 World Championships
- July 27 – August 3, 2025 (pool swimming)
- Singapore, Singapore
- World Aquatics Championships Arena
- LCM (50m)
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Continuing the pattern of unexpected results that the World Championships has seen thus far, the men’s 50 back prelims saw a number of familiar faces fail to advance or drop out of the race entirely.
Shaine Casas of the United States, who was the #3 seed in the 50 back coming into the meet, is out of the semifinals after finishing 20th this morning in 24.97. He tied with Brazil’s Guilherme Basseto, who was seeded 11th heading into the race.
Casas came into the meet with an entry time of 24.23, which he posted at the Pro Swim Series – Westmont back in March. That performance ranked him 3rd in the world this season prior to this morning’s races.
Earlier this week, Casas picked up a silver medal in the 200 IM with a lifetime best 1:54.30. He placed 19th in the 100 fly in 51.66, missing the semifinals like today.
China’s Xu Jiayu also missed the semifinals in the 50 back, placing 26th in 25.08. Xu was the #5 seed coming into the meet with a time of 24.38 from the Chinese National Championships in May, which ranked him 6th in the world this season. He already placed 11th in the 100 back (53.14) in Singapore.
Meanwhile Italian backstroke star Thomas Ceccon did not swim the prelims of the 50 back this morning. He was the #10 seed coming into the meet, entered with a 24.55. It took a 24.89 to qualify for the semifinals of the event.
Ceccon has already had a busy week in Singapore. He won silver in the 100 back with a 51.90 and picked up bronze in the 50 fly in 22.67. He also finished 17th in the 200 back (1:57.15), and placed 5th in the semifinals of the 100 fly (50.42) to advance to the final of that event, which he will race tonight.

Other swimmers have the grace to drop events they don’t want to swim after trials, even if they make the team. I’m so happy for Shaine and his amazing 1:54.3, but if he only wanted to do the 200 IM it would have been nice to open up the spots in this and 100 fly for someone who wanted to do compete
Who can do back in the medley relay? Yesterday I thought rumors about Urlando on back were insane but right now…
Casas has apparently noped out after being on Leon’s hip at the final turn in the 2 IM.