South Korean swimmer Kim Woo-min has grabbed the gold medal in the men's 400-meter freestyle at the ongoing world championships in Qatar, becoming the country's world swimming champion in 13 years.

Kim won his monumental gold medal with a personal-best time of 3:42.71 at Aspire Dome in Doha on Sunday (local time) at the World Aquatics Championships. Kim held off the 2022 world champion, Elijah Winnington of Australia, by 0.15 second.

Lukas Martens of Germany, the bronze medalist at the 2023 worlds, won his second straight bronze medal in 3:42.96.

Kim, 22, is only the second South Korean swimmer to win a world title, joining the two-time 400m freestyle champion Park Tae-hwan.

Park won his first title in 2007 and collected his second in 2011. Park, who also won the 2008 Olympic gold in the 400m freestyle, still owns the national record in that event with 3:41.53.

"It means so much to me that my first world championships medal was a gold medal," Kim said in a video interview released by his agency, All That Sports. "I didn't expect myself to win."

While some of the world's top swimmers are skipping the Doha event to focus on preparing for the Paris Olympics this summer, the men's 400m freestyle featured most of the top dogs. The only notable absence was the 2023 world champion, Samuel Short of Australia.

The next three best swimmers from 2023, Ahmed Hafnaoui of Tunisia, Martens, and Guilherme Costa of Brazil, all competed in Doha on Sunday. Kim had finished fifth last year with a then-personal best time of 3:43.92, and shaved 1.21 seconds off that mark in Doha.

By emerging as the world champion only a handful of months after winning his first Asian Games gold medal, Kim has established himself as a strong medal contender in Paris. Park remains the only South Korean swimmer to have won an Olympic medal. He followed up his 2008 gold in the 400m freestyle with a silver in the same race four years later, and he also won silver medals in the 200m freestyle in 2008 and 2012.

"Honestly, I wasn't even at my best physically, and I was still able to post such a good time," Kim said. "I think this performance will have a positive impact on my preparation. I am going to train hard for a medal at the Olympics, which will be an even bigger stage than the world championships. If I continue to put in the work, then I think good records will follow."

Hafnaoui won the 2021 Olympic gold medal in 3:43.36. In 2016, the 400m freestyle winning time, by Mack Horton of Australia, was 3:41.55.

Instead of conserving his energy for the final stretch on Sunday, Kim kicked into a high gear from the get-go and gave himself just enough cushion to hang on for the gold.

Kim had the fastest reaction time off the blocks with 0.61 second and had the second-fastest opening split at 25.32 seconds. He moved into the lead at the 100m turn and didn't look back.

Kim remained at a world record pace up to the 300m point. Kim lost a little steam over the final 100m but was able to stay in front of Winnington, whose final 50m split of 26.67 seconds -- 1.22 seconds faster than Kim's -- was not enough.

With Kim's gold, South Korea broke its own record for most medals at a World Aquatics Championship with three.

The two earlier medals came from diving, where Kim Su-ji won bronze in the women's 3m springboard and then teamed up with Yi Jae-gyeong for bronze in the mixed 3m synchronized event.