I get distracted when a doubles partner says "kill it", "put it away", (or something similar) during a point. It sort of breaks my concentration, i.e., it often wakes me up from the "unconscious zone". I don't want to say anything to him because it's not a regular partner (drop-in play -- random partner environment). What I really want to do is be mentally strong enough so that the chatter doesn't affect me. Any tips on how to do this?