The young Gers were punished by their ruthless visitors in the opening period, reducing the arrears after the interval through a terrific Ashton Scally solo effort and Chris Condy goal.
It brought the side’s three-match winning run to a halt as they now make the trip across the city in the first Old Firm of the campaign in seven days’ time.
Among the Rangers side this evening was the inclusion of Clinton Nsiala and both Dujon Sterling and Kieran Dowell as the duo stepped up their return from injury.
On the other side, a young St. Mirren outfit certainly didn’t lack in experience with Roland Idowu, who has featured over 30 times for the side’s first-team, in from the off alongside midfielder Fraser Taylor who was crowned League One Player of the Season last campaign for his performances in Arbroath’s title-winning side.
It was the hosts who fashioned the first opportunity of the contest when Dowell assumed free-kick duties from 30 yards out and wrapped a dangerous effort around a four-man St. Mirren wall and only inches wide of the far post.
However, the away side took the lead inside a quarter of an hour when Rangers failed to clear their lines from a set-piece delivery and the visitors had a man over at the far post to nod home from close-range.
Prior to that the Gers had a penalty shout when Luca Rankin latched onto a pass in-behind and appeared to be brought down by Grant Tamosevicius, but the referee waved the Rangers appeals away.
The hosts were even further incensed when Ben Hutton went down on the halfway line, allowing St. Mirren to break beyond the Gers ranks and win a spot-kick which they converted with aplomb to double their advantage.
St. Mirren were certainly the more confident of the two sides as a result, making it three before the half-time interval when Evan Mooney dispatched beyond Sam Reid.
It left Rangers with a mountain to climb in the second period as Ross turned to his substitutes bench to introduce Alexander Smith in place of Lawson.
The hosts emerged with a spring in their step as Condy tried his luck from distance, but his shot was ambitious and always sailing high and wide of goal.
They ought to have reduced the deficit moments later when Condy made an intelligent darting run back across the defence, drawing a save from Tamosevicius before Kyle Glasgow’s follow-up was blocked and Dowell, with the ball taking a wicked bounce, contrived to nod wide from close-range.
The goal they sought to make it an interesting final period arrived when Scally took matters into his own hands and skipped through a succession of St. Mirren challenges on the left-hand side of the penalty area before dispatching a sumptuous finish from a tight angle under the St. Mirren goalkeeper.
However, just as the hosts were beginning to build a head of steam they conceded for a fourth time on the evening, with Reid hapless to prevent an excellent curling strike into the far corner.
Rangers continued to push and netted again with six minutes remaining to make it an intriguing final stanza when Smith’s delivery from the left-hand side was bobbled by the visiting goalkeeper and Condy, as all good forwards do, pounced quickly to slam home from close-range.
Glasgow then shot straight down the throat of the St. Mirren goalkeeper from 25 yards and the speedy Max Cameron replaced Aiden Crilly, but time eventually ran out on the young side as the Paisley outfit prevailed with all three points.
RANGERS: S. Reid, Hutton, Sterling (Hynd, 60), Nsiala, Scally, Rankin, Crilly (Cameron, 90), Dowell (Young, 60), Glasgow, Lawson (Smith, 45), Condy
Subs not used: Millarvie, J. Reid, Caldwell
ST. MIRREN: Tamosevicius, Hutchison, Clark, McEvoy, Stoddart (Kiely, 76), Taylor (Lavery, 45), Rehman (Douglas, 58), Hodgkiss, Mooney, Idowu (Barr, 67), Dijksteel (Falconer, 58)
Subs not used: Innes, Morrow
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