Celtic Warriors snatched victory from the Scarlets with an injury-time penalty by outside-half Kerry Sweeney in a dramatic finale at the Brewery Field.
With just a minute remaining of normal time, outside-half Gareth Bowen had given the Scarlets the lead with his fifth successful penalty.
But the Warriors roared back to their sixth Celtic League victory in succession and, impressively, Sweeney's 45-metre kick was his first attempt at goal after replacing Neil Jenkins.
Early in the first half, Jenkins' amazing world record breaking run came to an end when he missed a penalty.
It was his first miss since last October against Munster in Limerick, since when he has kicked 30 penalties and 14 conversions without a miss for a best ever mark.
But it did not seem to matter as Maama Molitika burst away from a line-out to send fellow flanker Cory Harris over for what turned out to be the game's only try in the first half.
Jenkins converted and added two penalties with the Scarlets having two of their own from former Bridgend outside-half Bowen to make it 13-6 at half-time.
The second half was a very close affair, with the highlight a burst from full-back Barry Davis.
Davis broke free in his own 22, but was caught near the Warriors' line after a dramatic 80-metre chase by British Lions winger Dafydd James.
The Scarlets fought tenaciously to retain the title of the top Welsh side in the league, and two more penalties by Bowen set up that incredible finish.Reuse content