World Championships Relay Analysis: No One Stopping American Women in Medley Relay
The Tokyo Olympic final of the women’s 400 medley relay looks like a blip. Fueled by a career meet from Emma McKeon and an overperforming breaststroke split from Chelsea Hodges, Australia took down the United States for gold by 13-hundredths. But in every other global final dating back to 2016, the Americans have been golden, with most of the contests not particularly close.
Capping off that run was the final at last year’s Paris Olympics, where the American team won gold by almost three-and-a-half seconds and became the first group to ever crack the 3:50-barrier. In a reversal of their finishes in the individual backstroke events earlier in the meet, Regan Smith comfortably beat Australia’s Kaylee McKeown on the opening leg before Lilly King and Gretchen Walsh each had the fastest splits on their respective strokes. The Australian and Chinese freestylers out-split Torri Huske, but they were in a tight battle for placements while Huske entered with an insurmountable lead.
American backstroker Regan Smith — Photo Courtesy: Peter H. Bick
A similar result is expected at this year’s World Championships thanks to Smith, Walsh and Huske all entering the meet as the top swimmers in the world this year in their respective strokes. King has won gold every time she has raced this event in a major final, with the lone loss in 2021 coming when Lydia Jacoby handled breaststroke duties. There might be a new breaststroke swimmer this time, though; Kate Douglass came from behind to beat King in the 100 breast at King’s final U.S. Nationals, putting her in position to handle that stroke in this year.
That said, it won’t matter much is Walsh is two seconds clear of the competition on the butterfly leg, and that could be the case after she clocked 54.60 for a new world record in the 100 fly in May. Of the next three fastest swimmers in the Paris final, McKeon and Maggie Mac Neil are both retired while it’s unclear if Zhang Yufei will be in Singapore.
Below are the added-up times for the top countries in this event. Only 2025 season-best times are used here, but limitations of this analysis will be considered.
- United States: Regan Smith 57.46 + Kate Douglass 1:05.79 + Gretchen Walsh 54.60 + Torri Huske 52.43 = 3:50.28
- Australia: Kaylee McKeown 57.65 + Sienna Toohey 1:06.55 + Alex Perkins 56.42 + Mollie O’Callaghan 52.87 = 3:53.49
- China: Wen Letian 59.06 + Tang Qianting 1:05.57 + Yu Yiting 57.30 + Wu Qingfeng 53.27 = 3:55.20
- Canada: Kylie Masse 58.18 + Alexanne LePage 1:06.87 + Mary-Sophie Harvey 58.37 + Penny Oleksiak 53.89 = 3:57.31
- Italy: Anita Gastaldi 1:00.46 + Anita Bottazzo 1:05.82 + Costanza Cocconcelli 58.06 + Sara Curtis 53.01 = 3:57.35
- Great Britain: Lauren Cox 59.95 + Angharad Evans 1:05.37 + Keanna MacInnes 57.96 + Freya Anderson 54.09 = 3:57.37
- Japan: Miki Takahashi 1:00.71 + Satomi Suzuki 1:06.21 + Mizuki Hirai 57.04 + Nagisa Ikemoto 54.52 = 3:58.48
Based on times compiled so far in 2025, the U.S. women could take a shot at their world record from Paris, with the composite time only two-thirds of a second behind the time of 3:49.63 without subtracting for relay starts.
Australia looks like the clear No. 2 team, with strong veterans in McKeown and Mollie O’Callaghan bookending the relay. The team will also depend on some unfamiliar faces this year: Alex Perkins swam a huge best time in the 100 fly at the country’s selection meet to move to No. 2 in the world for 2025, and now she tries to fill the shoes of McKeon. Sienna Toohey, just 16 years old, heads to Singapore as the country’s top 100 breaststroker.
China is always in medal contention, and the front half of this year’s relay looks familiar with Wan Letian and Tang Qianting. But Zhang’s status is uncertain since she has only posted the third-best 100 fly time among Chinese swimmers this year, a far cry from the 55-second swimming which won her a world title in 2023. Meanwhile, Paris anchor Yang Junxuan is absent from the equation this year.
The composite relays show the next three teams at almost exactly the same speed. Canada has consistently contended for medals in this event, and the country’s team was actually in second place in the Olympic final before O’Callaghan and Yang overtook Summer McIntosh in the closing meters. McIntosh could return to anchor this year, and Kylie Masse will surely be out strong, but the loss of Mac Neil cripples this relay. The versatile Mary-Sophie Harvey came out of Canadian Trials in the top spot in the 100 fly, but she is nowhere near the speed required to contend for a medal. Similarly, Great Britain, Italy and Japan all have some solid legs but not the well-rounded relay needed to crack the medal race.
