2025 World Championships: Seven Takeaways From The Men’s 4×100 Medley Relay

2025 World Championships

• July 27 – August 3, 2025 (pool swimming)
• Singapore, Singapore
• World Aquatics Championships Arena
• LCM (50m)
• Meet Central
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• Live Results
• Live Recaps
  • Prelims: Day 1 | Day 2 | Day 3 | Day 4 | Day 5 | Day 6 | Day 7 | Day 8
  • Finals: Day 1 | Day 2 | Day 3 | Day 4 | Day 5 | Day 6 | Day 7 | Day 8

47-Low Isn’t What It Used To Be

Carlos D’Ambrosio had an excellent meet, but his final contribution is likely to be undervalued. In the final 100m of men’s world championship swimming this year, D’Ambrosio anchored an Italian team that had been a contender for gold and a near lock for the podium, featuring a wickedly fast front half of Thomas Ceccon and Nicolo Martinenghi.

The 18-year-old split 47.33, right in line with the 47.34 he split on the mixed free relay the night before. That is a great split at any age, but watching the race it was hard to believe he was hitting 47-low pace.

That was because he was next to Jack Alexy, whose 45.95 split made D’Ambrosio’s, the 4th fastest in the field and the 18th-fastest male split overall in Singapore, look positively pedestrian.

Alexy was not the only swimmer to go significantly faster than the Italian – Egor Kornev was 46.40 for NAB, and Josh Liendo was 46.90 for Canada.

After Pan Zhanle’s 45.92 last summer did something similar to Hunter Armstrong and Florent Manaudou to what Alexy’s leg did to D’Ambrosio this year, something is clear. A 47-low, which used to be the absolute best you could ask for, just doesn’t cut it at the sharp end any more.

Fly-And-Die Features Far More On The Relay

Elite 100 fly swimmers are able to come home either close to, or under, 27 seconds. That seems a fairly good barometer, with Ilya Kharun (26.75) in 2023 the only swimmer in the last five years to do so and not make the final. Within 12 months he was an Olympic bronze medalist, and another 12 months later he was a world bronze medalist as well.

Of the finalists in the last five summers, 47.5% (19/40) have come home under the mark, including all medalists bar two – Noe Ponti in 2021 and Josh Liendo in 2022. It should then come as a surprise that in the entirity of this event – heats and finals – there were only two sub-27 back ends.

They came from Ilya Kharun in the heats and Maxime Grousset in the final, and this is not isolated to this year. The Olympics saw exactly the same, with one in the heats (Ilya Kharun again) and one in the final (Caeleb Dressel).

Of the finalists from the individual 100 fly who then swam on this relay, all bar Maxime Grousset closed slower on the relay. Grousset was almost exactly the same at two-hundredths faster.

The majority of the speed on the fly leg seems to come from a faster first 50. That favors those swimmers who are back-half swimmers in the individual – Temple, Kharun and Josh Liendo are examples – rather than those who depend on front end speed such as Maxime Grousset and Nyls Korstanje.

Grousset is probably the best example. His 49.27 split is phenomenal tied for #2 in history with his own from 2023, but he was out 22.4 in both. He goes out 22.80 from a flat start, and getting down to 22-low, even from a relay start, is incredibly difficult. If he wants to take over the crown for the fastest split in history he will need to bring his back end to bear like Dressel did in 2021.

The World Record holder was 22.68-26.35 there to split 49.03. Given Grousset’s tactics and the nature of the relay leg, he may not be the one to crack that mark.

Canada Look Like The Next Big Thing

At the start of the last Olympic Cycle, most Canadian swim fans would have bitten your arm off if you’d told them they were a breaststroker away from contention in the medley relay.

They had just finished 7th in the Olympic final, only ahead of China thanks to a DQ, and were the only nation not to break 3:30. They had four solid splits – 53.3, 59.6, 51.0, 48.0 – but not even one that was elite.

This year they had two top-55 all-time splits (Kharun #11 on fly, Liendo #52 on free), an emerging backstroker in Blake Tierney who dropped half a second, and an 18-year-old breaststroker who looks primed to make some noise as soon as next year. The swimmers on their front two legs are improving rapidly – those on the back half are two of the best in the world already.

Canada broke their National Record in both heats and finals, and dipped below 3:30 to finish 5th, becoming just the 11th nation to do so. With a 59.9 breaststroke split and what looks like more to come on backstroke, further improvement seems inevitable and a podium could be in their future.

U.S. Show The Importance Of One Big Split

The U.S. have always had an elite backstroke presence to give them a platform to go off on this relay, but had Tommy Janton lead off this year in 53.37. With Josh Matheny splitting 59.00 on breaststroke, the U.S. hit halfway in 1:52.37 – two seconds down on the leaders and their slowest first 200 since 2011.

Dare Rose had an elite split of 50.30 on fly, but was still a second slower than Maxime Grousset and just behind Andrew Minakov. At that point, sub in Hunter Armstrong’s 47.19 anchor from last year and the U.S. finished in 3:29.86 – and in 5th place.

Instead, thanks to an otherworldly split from Jack Alexy, they took bronze. He was 1.24 seconds faster than Armstrong was, and the kind of gap that the very best swimmers can put between themselves and the world-class athletes they are competing with can make a relay like this.

Put in a Kyle Chalmers 46-mid on the anchor and the U.S. still misses the podium. A huge leg like Alexy’s can erase weaknesses elsewhere – Grousset’s fly and Peaty’s breaststroke cover(ed) weak legs on free and backstroke respectively on their relays – in a way that’s tough to match by committee.

One other way the importance of this was shown was that NAB did not quite crack the World Record, despite having four elite legs who all hit pretty much as well as could be expected. Caeleb Dressels 49.03 split was over a second quicker than Andrei Minakov was here in 50.17, so even a 57.92 from Kirill Prigoda on breaststroke and 46.40 from Egor Kornev on free were not enough.

Great Britain Should Aim To Peak In LA

It is a big what-if moment that the backstroker Great Britain were crying out for four years ago in Tokyo is now here. Add Oliver Morgans’s best time of 52.12 to Adam Peaty, James Guy and Duncan Scott’s splits from 2021 and you get a scarcely believable time of 3:26.00 from that relay. Even with the 52.74 he led off with tonight, they go 3:26.62 and steal both the gold and the world record from the U.S..

The team right now is one in transition, with no guarantee over who will be on the middle two legs in three years time. Peaty is aiming to contend for medals in LA, and has targeted the 100 specifically because of this relay. Aged 34, he is unlikely to be in 56-mid shape, but may also have some up-and-coming swimmers to watch out for.

Filip Nowacki had a fantastic European Juniors, breaking Peaty’s British Junior Record, Max Morgan is still only 17 and has a best of 1:00.10, and Greg Butler dropped a 59.11 split after entering the meet with a best of 59.93.

While James Guy has moved away from fly and Duncan Scott, Matt Richards and Tom Dean are all at least two years removed from their last sub-47 split on free, there is young talent pushing through on those legs as well. Jack Brown and Dean Fearn look like potential pieces on fly, while Jacob Mills or Gabriel Shepherd, who split 48.24 at just 16 last summer, are in line to break through on free.

Seven years after their last medley relay to truly contend, LA could be the combination of a last hurrah for the old guard and a coming out of the new one.

France Need A Freestyler

Here’s where France’s splits ranked in the field: 2nd, 3rd, 1st, 7th. That, if it even needed to be pointed out, shows a big hole in what has long been a strength for France – sprint freestyle.

They do have a 100 free finalist who has split 47.1 before, but their issue is that he is already swimming the fly leg.

France tested out that swimmer, Maxime Grousset, on the freestyle leg in the morning with Clement Secchi on fly duties, where the CN Marseille swimmer split 50.93 before Grousset anchored in 47.11.

Those are both solid-to-great splits, but when reverting to the tried-and-tested Grousset on fly order, he was 49.27. That is 1.66 seconds faster than an already-good split from Secchi, and to just match the morning’s back half evening anchor Yann le Goff would have needed to go just 48.77.

Le Goff was 47.99, more than half a second slower than any of the anchors from the top five teams and 1.59 seconds slower than NAB’s Egor Kornev, who blasted past to take the win. With Grousset so good on the fly, someone else needs to step up on freestyle if this team is to win gold.

That could be Rafael Fente-Damers, but the Texas commit was off his best in Singapore and, at just 19 still, is raw. He is the best hope right now of becoming the 47-low this team needs, but not a guarantee.

Poland Need The Real Masiuk To Step Up

Poland were just off the final this year, placing 10th in 3:32.83, just 0.29 seconds away. Dawid Wiekiera, Jakub Majerski and Kamil Sieradzki are all solid swimmers, capable of good-to-great splits – exactly what you need to make a relay final.

A big reason for their miss was Ksawey Masiuk’s backstroke leg. At 53.78, this was more than a second off the 52.67 he swam for 9th individually, and his slowest swim of the meet.

The more worrying aspect is that this is a theme. Only at the 2024 World Championships was he faster on relays than individually, and a big part of that was him bowing out in the heats of the 100 back.

Fastest Swims By Ksawery Masiuk At World Championships/Olympics, All Rounds

Masiuk is making a habit of adding time on the relay leadoff, and significantly. Poland has the team right now to make the final for the first time at a summer worlds since 2015 – they need him to find his individual form to help make it happen.