Glentoran came from a goal down to beat Carrick Rangers 2-1 at Taylors Avenue on Tueday.
The result means Carrick will be involved in the relegation/promotion play-off at the end of the season.
Both defences remained on top in the opening 45 minutes with TJ Murray firing the home side ahead just after the restart.
That lead lasted only two minutes as Jonathan Smith blasted home a sweet volley for 1-1.
The winner came from the visitors on 80 minutes with Curtis Allen in prime position to finish off a defence splitting pass from Stephen O'Flynn.
Meanwhile, Andy Mitchell scored twice as Dungannon Swifts secured a 4-1 win at Ballinamallard.
The breakthrough was provided by Ryan Harper on 24 minutes, but United hit back right away through Warner Mullan.
Mitchell grabbed his first on 31 minutes and then gave his side a two-goal cushion before Dougie Wilson headed in at the back post to make it 4-1.