Goals from Dean Jarvis, Mark Randall and Lee Lynch helped Larne defeat Portadown at Shamrock Park.
It took Tiernan Lynch's side just eight minutes to open the scoring when Jarvis connected with an inswinging corner from Ben Doherty to head unmarked past Harry Doherty.
Larne made it 2-0 just before the half-hour mark through Randall with a chip over the home keeper after Navid Nasseri found him on the edge of the box.
Both sides might have found the net before the break with Ronan Hale pouncing on a defensive error only to see his shot saved while Adam Salley skimmed the crossbar after getting past Cian Bolger.
Portadown pulled a goal back on 66 minutes. Substitute Sam Warde sent a ball into the box for Lee Bonis but the rebound fell for Ruairi Croskery to hook home.
And the home side almost levelled a few minutes after that but Warde's curling free-kick from distance fell just the wrong side of the post.
There was a flurry of activity in the closing stages with Andy Scott and Nasseri both denied by goalline clearances from Greg Hall and Adam McCallum.
Then, in stoppage time, Lynch made it 3-1 to Larne from the rebound after Thomas Oluwa saw his initial effort saved before, moments after that, Hall slid home Portadown's second with almost the last action of the game.