The Japan Swim came to a speedy conclusion in Tokyo at the weekend when Paris 2024 Olympic silver medalist Tomoyuki Matsushita led a sub-4:10 podium in the 400m medley: his 4:08.61 led the way ahead of Asaki Nishikawa (4:09.63) and Kosuke Makino (4:09.79).

Matsushita, the closest man to home-Games superstar Léon Marchand last summer led from go to gold through splits of 55.79, 1:58.97 and 3:10.19. Nishikawa held on for silver in the race for the last berth on Japan's team for the World Championships in Singapore this July and August.

The day before, Matsushita, 19, took the 200 medley in 1:56.35. All but one of the finalists got inside the 2min-mark, with Makino grabbing his own ticket to Singapore in a solid 1:56.80.

Matsushita is impressive on all four strokes but on freestyle he had a younger teenage rival to contend with. Tatsuya Murasa is one to watch: the 17-year-old set a Japanese high school record of 1:45.67 to win the 200m freestyle ahead of a 1:46.96 from Matsushita.

The last day of action in Tokyo also witnessed progress in the men's 1500m freestyle after a decade of stagnation. Kazushi Imafuku is 17 - and now a national record holder: his 14:50.18 took down the 14:54.80 at which Kohei Yamamoto had held the Japanese standard since the Japan Open back in 2014.

Imafuku clocked a best time at the 800m mark, too, his 7:52.57 the fifth best ever by a Japanese swimmer and not far shy of the 7:49.55 at which Syui Kurokawa has held the national record since nationals in 2021.