Late goals for both sides ensured a share of the spoils in a tense game at Oriel Park as Treaty United snatched a 1-1 draw against league leaders Dundalk.
It looked as if the Lilywhites had laid claim to the three points with an 85th-minute strike from Harry Groome, only for it to be cancelled out in added-on time by Mark Walsh to earn the Shannonsiders a draw.
Dundalk went close to scoring in the opening seconds of the game with a Daryl Horgan free-kick, which was met by Eoin Kenny at the back post, but the forward's header flashed wide.
Treaty defender Richkov Boevi was inches from scoring in the 14th minute, with his goalbound header from a corner being cleared off the line by the outstretched Enda Minogue, who was forced to make a vital stop.
Despite continued pressure, the Lilywhites failed to convert a series of chances as Treaty continued to look dangerous on the counterattack. Kenny once again had a clear sight on goal in the 30th minute but was unable to convert, while Lee Devitt struck the side-netting for the visitors moments later.
Sean McHale sent his headed effort just over the bar for Dundalk in the 55th minute from a Horgan free as the goal continued to elude the home side in the opening period of the second half.
McHale was then called into action to make an important block as Sullivan's strike from the edge of the area had to be deflected for a corner. The resulting set piece in the 60th minute saw Treaty almost squeeze the ball home, only for Aodh Dervin to make a vital intervention off the line.
Dundalk looked certain to score from a breakaway attack from midfield with Eoin Kenny setting Leo Gahxa down the right, but the Dundalk winger's low effort whistled past the post.
The home side would score late in the contest, with Groome finding the net in the 85th minute.
Treaty failed to clear their defensive lines from a Keith Ward corner, with the ball recycled on the left by Andy Paraschiv. He laid the ball to Groome with the Dundalk midfielder striking first time to rifle the ball to the back of the net, leaving Chambers flat-footed.
The action was yet to be concluded with Treaty scoring in added time to snatch a point with captain Mark Walsh latching onto the ball in the Dundalk area and squeezing his effort past Minogue to grab a point for the away side.
Dundalk: Enda Minogue, Sean McHale, Aodh Dervin, Daryl Horgan, Harry Groome, Dean Ebbe (Keith Ward 76), Leo Gaxha, Luke Mulligan, Vincent Leonard, Eoin Kenny, Shane Tracey (Andy Paraschiv 68).
Treaty United: Corey Chambers, Richkov Boevi, Lee Devitt, Colin Conroy (Stephen Healy 80), Yousef Maddy, Nikodem Kozlowski (Roy Lawlor 67), Evan O'Connor, Mark Walsh, Mark Murphy (Connor Willson 67), Eoin Martin, Karl O’Sullivan.
Referee: Lucas Keating.
Elsewhere, Cobh Ramblers narrowed the gap at the top to just four points following a comprehensive 3-0 win at UCD.
Barry Coffey's sixth-minute strike handed the visitors the perfect start against the Students at the UCD Bowl, and they doubled their lead in the tenth minute through Sam Bellis.
Coffey was then on hand six minutes before the break to bag his brace and secure the three points for Ramblers.
Bray Wanderers' title ambitions took a major hit as they went down 2-1 to Kerry as they remain in third place, nine points off the top.
Kennedy Amechi's opening-minute strike handed the hosts the early lead, and while Max Murphy levelled from the spot in the 52nd minute, Kerry would seal the victory through Abel Alabi's 87th-minute winner.
Longford took the points with a slender victory in Wexford, with Emre Topcu's sixth-minute strike the difference between the two sides, while Athlone Town and Finn Harps prop up the table following their scoreless draw.
