[Jiggling the cane like that could convey some message about respective physical conditions, or the appropriateness of challenging maybe-strangers to a physical showdown. It could do that.

Or, it could be interpreted as a gesture pointing out that this guy has his own wooden stick with which to hit balls, and imply an enthusiasm for doing so.]

Lacrosse, huh? I've never heard of it... Which must be why, you think you'd beat me so easily. [The question of cane use as a cane doesn't even enter into his defensive boastfulness. Not knowing the rules, for one, makes it harder to rule out what skills would be relevant.] But I'm a quicker study than that!