FUKUOKA -- Three South Koreans moved on to the next phase while others were sent packing in Day 1 of swimming at the world championships on Sunday.

Kim Woo-min made his second consecutive final in the men's 400-meter freestyle at the World Aquatics Championships in Fukuoka, Japan, with a new personal best time of 3:44.52. He finished sixth in the heats, with the top eight reaching the final set for Sunday evening at Marine Messe Fukuoka Hall A.

Kim Seo-yeong qualified for the semifinals in the women's 200m individual medley, finishing 14th among 16 qualifiers in 2:11.50. It was her best time of this season.

The semifinals are set for Sunday evening, with Kim trying to reach her fourth consecutive final.

In the men's 100m breaststroke, Choi Dong-yeol advanced to the semifinals after ranking 12th out of 16 qualifiers with a time of 59.94 seconds.

He must be among the top eight in Sunday evening's semifinals to become the first South Korean since 2011 to reach a world championships final in a breaststroke event.

Elsewhere, Baek In-chul was eliminated in the heats for the men's 50m butterfly, despite tying his national record time with 23.50 seconds.

Han Da-kyung finished 18th in the heats for the women's 400m freestyle, where only the top eight qualified for the final.

A duel for the ages has been set up in the women's 400m final, with the current world record holder, Summer McIntosh of Canada, going up against Katie Ledecky of the United States, the four-time world champion and 2016 Olympic gold medalist, and Ariarne Titmus of Australia, the 2019 world champion and 2021 Olympic gold medalist.

Park Su-jin ended in 28th place in the women's 100m butterfly heats, as the top 16 reached the semifinals.

In the men's 400m individual medley, Kim Min-suk checked in at 21st place, while the top eight earned their spots in the final.

South Korea placed 17th in the heats for the men's 4x100m freestyle relay, missing the final featuring the top eight teams. (Yonhap)