A Historical Study of the “Five-man Two-line Defense” in Japanese competitive basketball

Abstract

  This study focused on the defensive strategies employed in Japanese competitive basketball in the 1920s and 1930s with the intention of clarifying the process through which the “five-man two-line defense”, a type of man-to-man defense, became a mainstream tactic after first examining the factors behind the decline in the number of teams employing the “3-2 zone defense”, a defensive strategy first introduced by Waseda University.
  The study results can be summarized as follows.
1.  The 3-2 zone defense was introduced in Japan in 1924 and proved highly effective at the time; however it gradually fell from favor. The reasons for its decline included the use of high post play, an offensive strategy that proved effective against a 3-2 zone defense, an increase in the size of the court, and the fact that there were fewer leaders who could teach team members the difficult-to-learn 3-2 zone defense.
2.  Teams employing a five-man two-line defense man-to-man variation as a substitute for the 3-2 zone defense began to emerge in Japan from around 1926. However, this latter tactic had drawbacks due to the role of each position. For this reason, many teams adopted a five-man two-line defense zone defense formation, which is essentially the same as the nearest man-to-man defense, as it was able to eliminate the drawbacks of the five-man two-line defense man-to-man variation. The five-man two-line defense zone defense formation was a defensive strategy that was not significantly affected by high post play or the expanded court size, and that could be learned easily even when few leaders were available to provide complex tactical directions. As a result, the five-man two-line defense zone defense formation overcame the factors that rendered the 3-2 zone defense ineffective, and was widely adopted by domestic teams.