Over three days in late January, Alysa Liu turned into a sensation whose fame briefly reached beyond her sport.

Liu went from becoming, at age 13, the youngest senior national champion in U.S. figure skating history to appearances on TODAY and the Late Show with Jimmy Fallon, charming both viewers and the hosts.

And then, because of her age, Liu disappeared from not only the wider stage provided by those shows but also from figure skating’s stage until next season.

The situation is similar for the three young women, Anna Shcherbakova, Alexandra Trusova and Alena Kostornaia, then 14, 14 and 15, respectively, who swept the senior podium at the Russian Championships in December.

And for Stephen Gogolev, 14, senior silver medalist at the Canadian national championships in January.

At least the three Russians and Gogolev made the minimum age cutoff for this week’s World Junior Championships in Zagreb, Croatia, although Kostornaia withdrew for unspecified medical reasons. Liu is too young even for junior worlds.

But none of those five are old enough to compete in the senior world championships later this month in Japan.

That means the premier figure skating event of this season will be missing five of the best and most compelling skaters – at least as determined by national championship results – from three of the world’s traditionally powerful skating countries.