Mark Warburton remains on course for his first silverware as Rangers boss after his side booked their place in the Petrofac Training Cup final with a 4-0 win over St Mirren at Ibrox. Jason Holt fired his side ahead nine minutes before the break with his fourth goal in seven games before Kenny Miller added a second on 77 minutes.
Martyn Waghorn’s 18th of the season and a late Sean…