In the heats, Japan's Tomoru Honda, the silver medalist at the previous Olympics was eliminated.

Milák also won the event at the 2019 and 2022 World Aquatics Championships, but in 2023 he "hit rock bottom" and took a break from swimming.

[4][5] Finally, the rest of the spaces were filled by athletes who had met the Olympic Consideration Time (OCT), which was 1:56.36 for this event.

[8] Tomoru Honda, the silver medalist at the previous Olympics, slowed on the final 50 metres and did not qualify.

[9] Honda commented after exiting the pool: "[For some reason] my mindset was to play it safe, I didn't feel lethargic or anything.

Ilya Kharun, Noè Ponti, Estonian Kregor Zirk, Poland's Krzysztof Chmielewski, Italy's Alberto Razzetti and Austria's Martin Espernberger also qualified.

Switzerland's Noè Ponti had the third fastest 15 metre split, and Canada's Ilya Kharun the fourth.

[17] Over the rest of the first length (15–50 metres), Milák extended his lead over Marchand to 0.64 seconds and Kharun elevated himself to third.

[20] His 1:51.21 made him the second fastest of all time, ahead of the USA's Michael Phelps and trailing Milák's world record.