Kadoban

Kadoban is a term used in Go to describe a critical game in a multi-game title match series where one player is on the brink of losing the match. If they lose, they forfeit the title or the series. This concept is especially relevant in best-of-five or best-of-seven formats, where reaching kadoban signals a do-or-die moment for the player trailing in the series.

While primarily a Go term, kadoban is also used in shogi and sumo wrestling. In sumo, for example, an ōzeki (the second-highest rank) who loses a tournament faces a kadoban situation in the next tournament—if they fail again, they are demoted.

In Go, kadoban moments have led to some of the most dramatic turnarounds in professional play, making them unforgettable highlights in high-stakes matches.