Super sub Jordan Owens grabbed a brace to ensure Seaview remained an unhappy hunting ground for Glenavon.
The pre-game league leaders were restricted to chances from set pieces in the first half with the best of them coming from Guy Bates on 26 minutes. A big deflection made it dip more than Sean O’Neill was expecting, but luckily for the Crues it went over the bar.
And it was from a Glenavon free kick that Crusaders got the first goal of the game. Gareth McKeown’s low effort was blocked by the wall. The Crues broke away and Timmy Adamson muscled his way through the defence to fire into the far corner.
They could have had a second when Paul Heatley’s cross across goal evaded David McMaster.
Glenavon came out all guns blazing at the start of the second half and almost pulled level when Andy McGrory half-volleyed over.
But they were caught cold on 73 minutes when the Crues counter attacked with Paul Leeman crossing for substitute Jordan Owens to head home.
Former home favourite, David Rainey, hit the post with an acrobatic effort from a McKeown long throw-in.
The three points were sealed when Adamson’s cross was poked in by Owens as the home defence stayed static.
Crusaders: O’Neill, Leeman, Magowan, Coates, McClean, E. McAllister, Morrow, Adamson, Robinson, Caddell, Heatley. Subs: King, McMaster, Snoddy (McAllister 65), McCutcheon (Heatley 87), Owens (Caddell 65).
Glenavon: Coleman, Murphy, Kilmartin, Bates, Rainey, Patton, McGrory, Marshall, McKeown, McCabe, Singleton. Subs: Neill (Kilmartin 74), McCallion (Murphy 61), Lindsay, Farren (Patton 57), Hagan.