Persson swam in 2.04.01, a new season's best, which was the sixth best time in the trials on Friday.
- It felt quite relaxed the first half, then I had to struggle a bit at the end, he says about the performance in the swimming association's broadcast.
Erik Persson took silver in the 200-meter breaststroke at the long-course World Championships this summer, but missed the long-course EC in August.
At 09:51 Swedish time, he has a chance to win a new WC medal.
The Mix team missed out on promotion
The Swede Michelle Coleman also advanced from the trials in the 50 meter freestyle with a time of 23.94.
It was 20 hundredths behind Polish Katarzyna Wasick, who was fastest in the trials.
The Swedish mixed team missed a final place in the 4x50 meter freestyle by 19 hundredths and finished in ninth place in the attempt with a time of 1.32.34
Emelie Fast also swam trials in the 200 meter breaststroke.
But her time of 2.22.22 was not enough for a place in the final.
Likewise, Isak Eliasson did not advance from the attempt in the 50 meter freestyle with a time of 21.47.
CLIP: Highlights from Thursday's World Swimming Championships (December 15, 2022)
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Highlights from the World Swimming Championships in Melbourne, Australia.