Brighton and Hove Albion handed Arsenal their 3rd successive loss after beating them 2-1 in an English Premier league game.
Two first half goals from Dunk and Murray was enough for Brighton.
New Arsenal forward Pierre-Emerick Aubameyang scored one for Arsenal in the second half but that was not enough to salvage a point for the gunners.
This result piles more pressure on Arsenal manager Arsene Wenger as the club have not won a game in their last three matches.
Arsenal are currently 6th on the EPL table and are facing a possible miss on the top four.