Still it might have been a good thing he lost it. That allows him to get a new, possibly more interesting one. After all, the number of swords is limited to three. And the particular sword he lost wasn't as special as the other two: The original reminding him of the dojo master's daughter, who was his first rival, or the cursed sword that chose him. No doubt he will get a third sword at some point, and I'm hoping it's also somewhat special.