When this comic was published, the red army (fanatic socialists) called themselves as "Ashita-no-Joe". Also, when Riki-ishi died in the comic, the real funeral ceremony was held in Korakuen Hall, the boxing palace in Japan.
Personally, I like the second part of the story that Joe strives to overcome the loss of his undefeated rival and fight to death for the world champion belt.
Who knows tomorrow?
Legendary double Knocked-Out by "Cross Counter"