A late try left Portadown firsts on the front foot in Saturday’s Conference League challenge at Ballynahinch.
A positive start featured early offensive play before Daniel Tully broke the deadlock by moving over the line despite attempted Ballynahinch tackles.
Chris Cousens steered home the conversion and Diarmaid O’Kane then crashed over after a quick tap-and-go penalty.
Cousens made his mark and the Ballynahinch response featured a single penalty ahead of the half-time break.
Two converted tries within a 15-minute period afer the interval allowed Ballynahinch to hold the upper hand approaching the closing moments.
However, a final twist arrived as Portadown posted a last-gasp converted try for the 21-17 success.
Portadown seconds enjoyed an impressive return to form by romping home on a 92-0 tally in the derby date with Dungannon.
Thomas Johnston - selected as the leading player on the pitch - opened the scoring.
Craig Woods walked off the field of play having posted 27 points courtesy of one try and 11 conversions.
Stuart Lamb’s appearance produced a try, with hat-tricks apiece for both Calvin Chambers and Stephen Buckley.
Robert Ciack posted a try double - with one each for Aaron Winters, Jonny Hampton and Olivier Montels.
A commanding front-row display arrived from Matt Davison, Darren Thompson, Rab McClean and Mark Neilly.
Portadown thirds’ top-of-the-table city visit finished in defeat to Belfast Harlequins.
A frustrating afternoon for Portadown failed to spark into life as the Chambers Park men hit the road with a reshuffled side due to injury issues.
Unbeaten Harlequins extended the strong run of results with a commanding first-half display.
Additional injury problems left Portadown down to 14 men across the second half.
A reward arrived when Matt Quinn - a traditional winger operating at scrum half - scored the try converted by Marc Beggs - a traditional scrum half operating as out half.
Portadown fourths finished down by 39-10 in the home test with Ards.
Karl McQuaid, Carlton Bell and Simon Adams worked hard from the start but Ards - boosted by the experience of Andy Matchett, a former European Cup winner - held half-time control.
Rory McCreesh slotted over a first-half penalty - with Richard May and Conor Creaney impressive after the break.
Bell posted his debut try to cap slick teamwork before William Craig, Simon Lappin and Billy Newell combined at set-piece play.
McCreesh finished with five points, a tally matched by Bell.