How do I express my displeasure at a player

I like the emotes that you can do and I like the simple easy to use quick chat like thanks and good game. But how do you tell them they are being a cunt?

Most duals I've fort have been fair fights I've either lost or I've won and I've enjoyed all of those. But what happens when the other player just wants to run back and forth hitting you then retreating until he won the duel. At no point during that boring death by a million cuts could I tell them how dick-ish they were being!