2025 World Championships: Day 4 Prelims Preview

2025 World Championships

• July 27 – August 3, 2025 (pool swimming)
• Singapore, Singapore
• World Aquatics Championships Arena
• LCM (50m)
• Meet Central
• How To Watch
• SwimSwam Preview Index
• Entry Book
• Live Results
• Live Recaps
  • Prelims: Day 1 | Day 2 | Day 3
  • Finals: Day 1 | Day 2 | Day 3

Day 4 Prelims Heat Sheet 

The last individual event of the morning, the women’s 200 fly, sees Canada’s Summer McIntosh look to chase the white whale that is the WR. Set back in the super-suited era, Liu Zige‘s 2:01.81 has eluded being eclipsed for the past 15 years. The Canadian, already a champion twice over this week, McIntosh posted the 2nd fastest time ever in the event at Canadian Trials. With only 27 entrants in the event, McIntosh certainly does not need to push the pace that fast this morning, and neither likely will the #2 seed Regan Smith, who has the 50 back prelims before this race. Do keep an eye out for China’s Yu Zidi, in the first heat. The #6 seed, who is just 12 years old, just missed out on making the podium in the 200 IM, finishing 4th in the finals.

As mentioned in the paragraph above, Smith is entered in the 50 back prelims as well, where she is the #2 seed, behind the newly minted American Record holder, Katharine Berkoff. The pair who collected silver and bronze last night in the 100 back, will look to hold a charge from the ever dangerous pair of Canadians Kylie Masse and Ingrid Wilm. The French pair of Analie Pigree and Mary-Ambre Moluh, too, are seeded high up but will have to contend with 50 specialist Lauren Cox of Great Britain, who, like Pigree, has podiumed in this event before.

The men’s 100 free, the crown jewel of men’s sprinting, is expected to be a very fast prelim. The top seven from Paris return to the field with Pan Zhanle, who set the WR at the Olympics the top seed. However, Pan has yet to show what he is fully capable of this season, as David Popovici and Jack Alexy are the only two swimmers this season, so far, to have recorded times under 47. Olympic Silver medlaist, Kyle Chalmers too has looked strong and in both the prelims and finals of the men’s 4×100 free relay outdueled Pan on the anchor leg.

Similar to the 200 fly, the men’s 200 IM sees Olympic Champion Leon Marchand begin his attempt to take down the World Record. Set back in 2011 by Ryan Lochte, it was one of the first World Records to be broken from the super-suited era, but has withstood the test of time since then. Marchand came within .06 of it at Paris, and scratched the 200 fly pre-meet to focus on this event. Joining him in hunting that record are a cadre of his training partners, as the #3, #4, and #7 seeds, Carson Foster, Shaine Casas, and Hubert Kos, are all based out of the University of Texas with Marchand. The group of four will be hard-pressed to top the field as Olympic medalist Duncan Scott and Wang Shun will be looking to break up the party.

The final event of the morning is a massive enigma as the mixed medley relay with it endless line-up combinations concludes the session. The American quartet of Ryan Murphy, Nic Fink, Gretchen Walsh, and Torri Huske set a new World Record in Paris, but with the front end absent, and sickness abound amongst the team,  your guesses about the composition of the relay are as good as mine. The Americans are not alone, however, in this situation, as their closest competitors, China and Australia, too, are dealing with questions about line-ups with doubles and a lack of key legs plaguing each of them.

Top Seeds

• Women’s 50 Back – Katharine Berkoff (USA)
• Men’s 100 Free – Pan Zhanle (CHN)
• Men’s 200 IM – Leon Marchand (FRA)
• Women’s 200 Fly – Summer McIntosh (CAN)
• Mixed 4×100 Medley Relay – USA