Celtic extended their lead at the top of the Clydesdale Bank Premier League to five points with a 1-0 win over St Mirren.
Kris Commons came off the bench to secure the victory after the Hoops had largely served up a drab affair at Parkhead.
Commons was thrown into the action in place of Freddie Ljungberg with 20 minutes to go and his introduction had the desired effect for Celtic.
Shaun Maloney was the provider with the pass that was collected by Commons 12 yards out before he lashed past the grasp of Gallacher with 79 minutes on the clock.
Saints could have snatched a late leveller but John Potter fired wide in the final minute with their best chance of the game.
Celtic's title rivals Rangers will be seeking to reduce the deficit again when they travel to Hamilton on Sunday.