Blackburn made it back-to-back wins to keep up the pressure on the play-off chasers by defeating QPR 2-1.
Captain Darragh Lenihan settled matters in the 30th minute with a thumping header, and Tony Mowbray's men also showed their defensive mettle by repelling late pressure from the division's second-best attack.
It is Blackburn's fifth win in their last eight home games, and after making it 10 unbeaten at Ewood, they closed the gap on the top six to four points.
For Mark Warburton's side, their porous defence once again let them down, conceding a winner that was all too easy to score.
Their away form is worrying – they have lost their last four on the road, conceding 11 goals, form that must improve if a play-off tilt is forthcoming.
Rovers were unsurprisingly named the side that beat Sheffield Wednesday 5-0. QPR were without top scorer Nahki Wells – Hugill replaced him.
It took 10 minutes for Rovers to continue where they left off at Hillsborough, when Joe Rothwell's wonderful pass picked out Armstrong, who cut in from the left to curl a sumptuous 25-yard effort in off the post.
Rangers regrouped and Hugill displayed the quality needed to replace 15-goal Wells in the 22nd minute as he combined brilliantly with Ilias Chair before delicately lifting the ball over Christian Walton for his 11th this season.
Luke Amos blazed a volley over for the visitors as the chances flowed, but Rovers re-established their superiority on the half hour through Lenihan's second in as many games, a powerful far post header to convert Rothwell's corner.
Kelly produced a fine save to keep his team in the contest eight minutes after the restart, tipping Adarabioyo's side-foot shot behind, before the defender nodded the resulting corner wide.
The threat at the other end remained, and Bright Osayi-Samuel glanced a header just wide on the hour mark.
Chances did not flow as freely in the second half but Rangers put the pressure on as the game progressed, with former Rover Todd Kane volleying over from an ambitious angle.
At the other end, Gallagher should have made it two in two but planted a header wide when well placed.
Substitute Olamide Shodipo had a late chance, but headed straight at Walton, as Blackburn secured the spoils.