There is a joke that table tennis has difficulty levels just like a video game: Easy, normal, hard ¡ª and China.

For decades, China¡¯s supremacy in the paddle-and-ball game, also known as ping pong, has gone unquestioned. For just as long, Japan ¡ª often seen as its greatest threat ¡ª has been striving to upend the status quo.

Last month, two-time Olympian Tomokazu Harimoto stunned China¡¯s reigning world champion, Wang Chuqin, 4-2 in the men¡¯s singles final to win the WTT Champions Yokohama title. Harimoto made it clear that he sees the victory as being a watershed, saying it was like ¡°opening a hole in a large wall.¡±