Carmarthen Quins headed to Broadacre, Dunvant, for the sixth round of the Super Rygbi Cymru campaign.
In a game that saw the lead transfer from team to team, it was Quins who drew first blood in the historic fixture, with Quins heading to Broadacre for the first time.
Winger Steff Evans crossed the whitewash after 13 minutes to open the scoring.
Swansea hit back with a converted try before half time to head into the changing rooms ahead 7-5 at the break.
The second half began with a try for hooker Isaac Young, putting the Quins back in the lead. Elis Price added the conversion to bring the score to 7-12.
Just minutes later, Swansea hit back with a try from Jamie Cox, with Josh Phillips adding the conversion.
With the score at 14-12 it looked as though Swansea would clinch their fourth victory of the 2025-26 season, but Quins had other ideas.
A final minute try from centre Gabe McDonald put the Quins back in front. Swansea had the opportunity to level the score but missed a crucial penalty.
Final score: Swansea 14 Quins 17
Table after Round 6
