Jermain Defoe's 16th goal of the season saw Rangers navigate a way past stubborn St Mirren's roadblock tactics to claim a hard-fought win.
Saints boss Jim Goodwin stuck by his promise to park "two buses" across Vaclav Hladky's goal as he looked to put the brakes on Rangers' title charge.
It did not make for a pretty spectacle but boss Steven Gerrard was relieved to see Defoe stab home the winner 11 minutes before the interval as his side kept themselves on track.
It was at this stage of the season last year that the wheels came off Rangers' title bid as they hit the skids at Rugby Park.
But this victory keeps the Light Blues two points behind Celtic with a game in hand, while Saints now sit just a point above the relegation zone.