Robbie McDaid's equaliser early in the second half earned Glentoran a draw at Inver Park - the third time Larne and the Glens have failed to be separated over 90 minutes this season.
Games between the two sides have invariably been tight affairs - including last month's County Antrim Shield final, which the Invermen won on penalties - since both clubs enjoyed investment in recent years.
Last night's game was no different, as the Glens stretched their unbeaten run to six games.
Jeff Hughes tapped the home side into the lead midway through the first half, but McDaid popped up with the leveller two minutes into the second half.
It was the home side who looked likelier to win it, but they couldn't find the winner.
There was an early scare for the visitors when McDaid went down clutching a shoulder in the third minute, but after some treatment the former Leeds United man was able to continue.
The opening exchanges were played at a high tempo, but it took until the 14th minute for the first opportunity. Tomas Cosgrove played a clever one-two with Marty Donnelly on the right flank and that allowed space to open up inside the box, but his shot was deflected wide by the alert Patrick McClean.
The opener arrived on 24 minutes. After a momentary floodlight failure, Cosgrove let fly from 30 yards, with his effort deflected well wide for a corner.
From the resulting set-piece, Donnelly curled in an inviting in-swinging corner which found Hughes in the six-yard box and he gladly tapped home.
The Glens' first chance came on 28 minutes when Paul O'Neill let fly with a fierce drive from 25 yards which stung the palms of Conor Devlin.
With 39 minutes gone, John Herron almost got bragging rights against the club he left a year ago, but the Scottish midfielder's shot from 20 yards was tipped over by Dayle Coleing.
The Glens should have been level on 40 minutes. Great work by Chris Gallagher delivered the ball on a plate for McDaid, but he stabbed wide.
The equaliser arrived just two minutes after the break.
Marcus Kane - on his 300th appearance for the Glens - sent in a searching cross, which was flicked on by Gallagher into the path of McDaid.
The striker timed his run to perfection, nipped in behind Josh Robinson and flicked the ball past a stranded Devlin.
Larne managed to stem the tide and had two good chances inside the space of three minutes. First, with 59 minutes on the clock, Hughes came within a whisker of his second when, after surging into the box, his stinging shot drew a save from Coleing.
Three minutes later, substitute Mark Randall almost scored with his first touch.
Cosgrove and Donnelly combined well again on the right flank, with the former crossing for Randall, but the former Arsenal man's looping header came back off the top of the crossbar.
After two late penalty shouts for Larne, referee Tony Clarke produced a red card for substitute Andy Scott for his protests.