That was the first time I've seen this, though not the first time I've heard of it; as it was mentioned in the "Projects" section of 3D world though I cannot remember the issue number.
It seems that this fight is one that should not have taken place, in the first instance the Samurai in red creates hostile intent by drawing his Katana form its Sire the Samurai in Blue decides that there is no reason for a fight to take place between the two of them and backs off.
By this action the Samurai in red must have felt by this action by the Samurai in Blue was both an act of cowardice but more fundamentally a slight on his honor giving the Samurai in red no choice in his mind but to attack: the fight that ensues then works on two fundamental levels. The first of these as stated is to avenge a perceived slight of honor (Samurai in red) the second of these is self defense (Samurai in Blue).
Regards to you.
Cyber_Angel