Coleraine debutant James McLaughlin gave the Bannsiders victory over the Glens as the substitute hit the only goal with his first touch of the game.
Glens keeper Elliott Morris tipped over a Garth Falconer strike in a poor first half of few chances at the Showgrounds.
Morris denied Sammy Morrow and Ruiari Harkin before McLaughlin made the breakthrough eight minutes from time.
Morris failed to hold Falconer's deflected cross and McLaughlin was perfectly placed to poke home.
It was a low-key first half in Coleraine although there was controversy in the opening seconds.
Glens striker Curtis Allen was challenged by David Ogilby in the box and claims for a penalty were turned down by referee Raymond Hetherington.
There was more frustration for Allen when Adam McMullan nipped in with a tackle as the forward was about to shoot on goal.
Coleraine upped the tempo after the break and Morris kept out the hosts until McLaughlin won it in a memorable debut display.