Second half goals from Mikael Mandron and Olutoyosi Olusanya proved the difference for the Paisley outfit as the Gers’ five-match winning run in the league was brought to a halt.
The Gers began with two changes to the side from last weekend’s triumph at Tynecastle, welcoming Cyriel Dessers and Robin Propper back into the team.
There was a heart-in-mouth moment just seven minutes into the contest for the hosts when a wayward pass out of his own six-yard area from Jack Butland found the feet of Jonah Ayunga, although the Gers goalkeeper was able to recover his position in time to thwart the forward’s driven effort.
Stephen Robinson’s side had set their stall out and their defensive block was certainly going to be difficult to pierce for the Light Blues.
Indeed, Vaclav Cerny was the first to fashion a shot in anger as the Czech winger jinked inside and forced Zach Hemming into a stop down to his left.
A wicked delivery from Hamza Igamane then almost found Propper at full stretch at the far post, before the Moroccan took it upon himself on 25 minutes to pounce on a slack pass in the St. Mirren ranks and cannon an effort off Alex Gogic and out for a corner.
Ryan Alebiosu would stand up a cross for Mikael Mandron, booked moments later for a foul on Nico Raskin, to head over in a rare sighting at goal for either team in the opening period.
The Paisley outfit have proved obdurate opposition for the Gers this term – earning a victory at the SMiSA Stadium on Boxing Day – and there was little evidence in the opening period to suggest it wasn’t going to be another tight affair.
Rangers were indebted to Propper five minutes before the interval when the Dutch defender produced a terrific sliding challenge to thwart Ayunga’s flick at the near post from Alebiosu’s low delivery.
The game then sparked into action on the stroke of the interval when Igamane was shown a straight red card by referee Nick Clancy for a foul on Mark O’Hara.
Replays, however, showed the Moroccan making clear contact with the ball and, after a trip to the pitchside monitor, the decision was overturned to a yellow card.
Rangers emerged for the second half in search of an opener and Igamane went close when he combined with Dessers before he was crowded out from a tight angle.
However, the deadlock was broken by the visitors moments later when the Light Blues failed to deal with a route one ball and Mandron was allowed to latch onto Ayunga’s flick-on and dispatch confidently into the bottom corner beyond Butland.
Clement’s side were offered a brief reprieve when the referee blew for a foul on Clinton Nsiala, but VAR saw no infringement from the St. Mirren goalscorer and Rangers, as a result, were now chasing the game.
A tantalising delivery from Jefte almost engineered an immediate response, before the Gers boss turned to his substitutes bench to replace Igamane with the returning Danilo.
Raskin stung the palms of Hemming from distance shortly as Rangers looked to up the intensity in search of a leveller.
An intricate move involving the substitute Danilo ought to have fashioned an equaliser for the hosts, but Cerny lashed wide on his unfavoured right side and there was no trouble for Hemming between the posts.
Rangers then had a mountain to climb 20 minutes from time when St. Mirren doubled their advantage through Olutoyosi Olusanya, who got the better of Nsiala and lifted a left-footed finish beyond Butland.
Clement sent for Tom Lawrence and Nedim Bajrami from the bench, but it was too little, too late from a Rangers perspective as St. Mirren closed out a rare victory at Ibrox.
RANGERS: Butland, Tavernier, Propper, Nsiala, Jefte, Raskin, Diomande (Bajrami, 71), Igamane (Danilo, 57), Cerny, Hagi (Lawrence, 71), Dessers
Subs not used: Kelly, Ridvan, Fernandes, McCausland, Rice, Curtis
ST. MIRREN: Hemming, Alebiosu (Bwomono, 65), Taylor, O’Hara, Ayunga (Olusanya, 65), Mandron, Gogic, Boyd-Munce (Smyth, 65), Fraser, John (Tanser, 90), Phillips (Kiltie, 74)
Subs not used: Urminsky, Idowu, Oseni, Kenny