The teenager swam a time of two minutes 7,01 seconds at Nagaragawa Swimming Plaza in Gifu Prefecture to beat the mark of 2,07,28 which Daniel Gyurta of Hungary recorded to win 200m breaststroke gold at the London Olympics.

“I am looking forward to next year’s world championships,” the 18-year-old schoolboy world junior champion told the Kyodo news agency after his record swim.

“I want to be a successor to Kitajima-san, a swimmer I look up to. I think I can cut it in the 200 at the world level and want to challenge in the 100, too.”

Kitajima, who will be 30 next Saturday, completed the 100 and 200 metres breaststroke double at the Athens and Beijing Olympics but finished outside the medals in both events in London.

Yamaguchi narrowly missed out on a trip to the Olympics but had already marked himself out as a talent to watch by clocking faster times in winning last month’s Japanese high school championships than Kitajima managed in London.