Blackburn failed to lay a marker down in the race for the top six as they could only draw 0-0 with a stubborn Stoke.
Tony Mowbray's men had a golden opportunity to close the gap on the play-offs to two points after defeats for Bristol City and Preston but, in the first of an Ewood double-header, they were frustrated by a resilient defensive display that involved notable second-half saves from Jack Butland.
Rovers are still well in the play-off mix but will see this as a missed opportunity, not dissimilar from their pre-Christmas stalemate with Wigan, despite having lost just once in nine matches.
Michael O'Neill's side are closer to the bottom three than they were at the start of the evening, but it may turn out to be a vital point, ending a run that has seen Stoke lose six out of their previous eight on the road.
Rovers started full of confidence, with Armstrong's shot fumbled by Butland before the offside flag saved his blushes, and Ryan Nyambe whistled a shot wide in uncharted territory for the right-back.
The returning Rothwell had the best chance of the half in the 16th minute, but a deft touch was needed to lift the ball over Butland following Gallagher's touch and the midfielder's flick was too heavy.
Unsurprisingly for a team that had shipped eight in their last two away games, Stoke tried to stay defensively compact and disciplined, but also had their moments at the other end – Nick Powell in particular, as he failed to connect with an inviting Jordan Thompson corner, while Tom Ince fired over after a quick free-kick caught Blackburn napping.
The second half almost saw an opener within the first five minutes when Darragh Lenihan lifted an inch-perfect pass towards the onrushing Gallagher but Butland stood tall and parried the striker's attempted lob.
Action came at both ends, as Armstrong slalomed between Tom Smith and Ince before drilling a near-post shot that forced Butland into a fine low save, while the impressive Tyrese Campbell's 25-yard effort was repelled by Christian Walton.
That was as good as it got, despite the pressure applied by the hosts. Lewis Travis hammered woefully wide late on and Danny Graham saw a shot deflected wide, as the hosts failed to find the composure or chance to convert their late dominance.