Eric Daniel said:The samurais did not nessecerely use jujutsu when they were disarmed. They did sometimes use jujutsu to deploy there sword and kill there enemy. For example, If there was a battle one on one and a samurai went for his sword, the opponent did not want to die so the opponent would grab the samurai's right hand or something of that sort. Because of this the samurai would have to use jujutsu to deploy there weapon.
The samurai tended to battle with halberds. The sword was a backup weapon.
I believe jujutsu was more for day-to-day use than battle.