Middlesbrough ended Bristol City's unbeaten start to the Championship season, with the Robins also knocked off the top of the table by Reading in defeat at Ashton Gate.
George Saville pounced on a howler between goalkeeper Daniel Bentley and defender Taylor Moore to nip in and slide the ball into the net on 73 minutes for the only goal of the game.
It felt as though it would take a moment of class or a mistake to come up with a winner as chances were few and far between, and in the end it was overplaying by Moore - who scored an own goal in last season's meeting - that handed Saville the chance to strike.