Huddersfield Town moved to within one point of the Championship's automatic promotion places as they dented Middlesbrough's play-off hopes at the Riverside stadium.
Naby Sarr opened the scoring for the visitors just before half-time, nodding home Jordan Rhodes' header across goal following a Sorba Thomas wide free-kick.
And Rhodes rounded off the win against his old club with a composed finished on the counter-attack on the hour mark having been played through by Lewis O'Brien.
Middlesbrough came closest in the 88th minute when Riley McGree struck the underside of the crossbar, but were otherwise toothless in attack.