Rangers defeated Motherwell 2-1 at Hampden Park in front of 37,077 fans to set up a Premier Sports Cup final meeting with Celtic on Sunday December 15.
Andy Halliday gave the Steelmen the lead in 25 minutes when he converted a Steve Seddon cross but Philippe Clement's side turned things round after the break.
Connor Barron played in Cyriel Dessers to equalise in 49 minutes and Nedim Bajrami grabbed the winner with nine minutes left after being set up by man-of-the-match Vaclav Cerny.