It's no surprise that teenage athletes make continuous improvement — day to day, week to week — in their respective sports.

For example, 19-year-old Ryosuke Irie's progress has been exceptionally fast and changes his status from a dark horse to one of the favorites for this summer's FINA World Swimming Championships in Rome.

Irie nearly broke the world record in the men's 200-meter backstroke final with a time of 1 minute, 54.02 seconds, 0.08 seconds behind American Ryan Lochte, in the National Swimming Championships in Hamamatsu, Shizuoka Prefecture, last weekend.