Barry Town United are through to the Nathaniel MG Cup final for the first time since 2017 after beating Cambrian United 3-0.
Steve Jenkins' men set up a showpiece with holders The New Saints, which will be played in Bridgend at the end of February.
It will also be their first final in nearly three years after clinching the inaugural Welsh Blood Service Cup during the 2022-23 season.
Much had been made in the run-up of the semi-finals of Barry's opponents, the Cymru South leaders, who had only been beaten twice in the league.
As such, Cambrian United held out until the stroke of half time, when a setpiece from Eliot Richards was headed in by Will Richards to edge the four-time winners in front.
Barry doubled their lead when an Eliot Richards shot from distance was softly blocked by home keeper Morgan Davies, with Ollie Hulbert on hand to score from the rebound nine minutes after the break.
Ben Margetson wrapped up the win on 78 minutes, beating a goalmouth scramble for Owen Cuddihy's shot to slot past Davies and confirm Barry's place in the final.
Earlier on Saturday, TNS beat Cymru North leaders Llandudno 2-1 with goals from Dan Williams and Jordan Williams to keep the Cymru Premier leaders on track for a record 12th league cup.
The first showpiece of the Welsh domestic season will be played at Penybont's Dragonbet Stadium on Saturday 28th February (kick off at 5.30pm).
Coincidentally, Barry travel to Penybont on Tuesday night for a Cymru Premier derby - with their bid for a top six finish still firmly in the balance - before returning to Jenner Park next Saturday to face Gresford Athletic in the fourth round of the Welsh Cup.
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