For all Middlesbrough’s dominance and quality on the ball, QPR will have felt slightly aggrieved as to how they found themselves 2-0 down.
Both Strelec’s opener and Browne’s headed goal came with more than a hint of fortune.
Morgan Whittaker’s shot deflected in off Strelec’s elbow to give the visitors the lead, while the second goal came from a corner that replays showed should have been given as a goal kick after clearly going out of play off Jeremy Sarmiento rather than the challenge of Ronnie Edwards.
But from their overall play, Boro were well worthy of the lead and there was nothing controversial about the third – which was a thing of beauty.
Picking up a pass from Conway, Middlesbrough captain Hackney took a touch before bending brilliantly around the dive of Joe Walsh and in off the far post.
QPR substitute Tylon Smith’s clumsy challenge sent Conway to the deck, with the Scotland international squeezing the spot kick just below the dive of Walsh, with the Rs keeper getting a hand to it.
Boro host Charlton Athletic and Bristol City next before a visit to Blackburn, followed by a potentially huge match in the promotion race against Millwall at the Riverside on Friday, 3 April.
Julien Stephan’s QPR side have now lost four of their past five games but have a comfortable 12-point cushion to the drop zone.
With a 10-point gap between them and the play-off places, Stephan will be keen to ensure their season does not fizzle out with little to play for.