Glentoran moved up to fourth in the Premiership table as they edged out Glenavon in Tuesday night's encounter.
Glenavon will rue a missed first-half penalty as Elliott Morris saved Guy Bates' effort in the 26th minute.
Ciaran Martyn missed two further Glenavon chances before Andrew Waterworth put Glentoran ahead on 67.
Stephen Carson curled in Glentoran's second from a 25-yard free-kick on 72 before Martyn pulled a goal back for the visitors in injury-time.
Glenavon, who went into the game after hammering Ballymena 7-0 on Saturday, were awarded their first-half penalty after Jimmy Callagher was adjudged to have infringed.
However, Morris moved smartly to tip away Bates's effort out for a corner.
The remainder of the first half was low key as both sides struggled to create openings.
Martyn missed two chances in quick succession in the third quarter as he headed over and then was denied by Morris after being played in by Brendan Shannon.
Waterworth put the Glens ahead on 67 with a composed finish after running onto a long ball.
Carson doubled Glentoran's lead five minutes later with a curling free-kick which went in off the post.
As Glenavon started to chase the game, Waterworth had a chance to extend Glentoran's lead on 79 minutes but was superbly denied by Davy O'Hare.
Glenavon player-manager Gary Hamilton crossed for Martyn to score in the first minute of injury-time but Glentoran had done enough to take the three points.
The win moves Glentoran above Coleraine in the table and Eddie Patterson's side now look virtually assured of a top-six spot.