sentences:  This tradition declines and disappears during the Sengoku period as each side prepared trained armies in thousands or even tens of thousands making the single combat have a limited, if any, effect on the outcome of the battle.In Russia, single combat is known as "bash na bash" (an old Russian expression meaning "one-on-one"), substituting a fight between champions for a full-scale battle was a traditional way to avoid the bloodshed of an internecine war.The leaders of the opposing "druzhinas" or other armed groups either rode towards the centre of the battlefield or sent messengers to negotiate whether the two most skilled fighters or the leaders themselves would engage in single combat, usually to the death.