Martyrs fans group @merthyrnoise have posted video footage of an emotional win at Ninian Park.
Merthyr Tydfil FC won 4-1 in a Welsh Cup tie against Cardiff City away almost three decades ago and striker David Webley fired a hat-trick.
Ebbw Vale-born goals ace Webley had two spells playing for the Martyrs, competing in Conference and European football.
Webley, now aged 53, also played for Uwic Inter Cardiff, Chesham United, Newport County, Ebbw Vale, Carmarthen Town and Rhayader Town.
Former Cardiff City players Terry Boyle and Paul Giles were in the Martyrs team and the win brings back great memories for fans who made the trip to Ninian Park for the third round cup clash.
Goal poacher Webley fired Merthyr in front before a handball by Boyle conceded a penalty and Chris Pike equalised from the spot.
Webley scored his second and Boyle made amends for his handball, heading home from a free-kick lifted into the penalty area.
Giles created the chance for Webley’s third thanks to a long run and left-foot cross. Wesley gained half a yard on his marker and sent a downward header bouncing into the net.
The Martyrs, with hugely successful manager Lyn Jones in charge, were overjoyed with their win, but their Welsh Cup ended in a 1-0 fourth round defeat against Swansea City.
The triumphs of Jones and his Martyrs included winning the Welsh Cup, beating Italian club Atalanta in the European Cup Winners Cup and winning the League title to earn promotion to the Conference.
The Merthyr Town team of 2017-18 are in action on Saturday when they play Farnborough away (3pm).