It was another nail-biter at the Parc, with the DHL Stormers holding on to claim a 29-17 victory to boost their BKT URC play-off hopes.
In a match that swung in momentum throughout, Scarlets threatened to claim a seventh successive league win late on when replacement Archie Hughes burst through towards the line.
But the men from Cape Town managed to withstand the home assault to come away with a vital bonus-point win.
With a side stacked with Springbok talent, Stormers flew out of the blocks with a quickfire try double through wing Ben Loader and veteran flanker Deon Fourie putting them 12-0 ahead after 18 minutes.
Scarlets had plenty of opportunities in the opening half and eventually the pressure paid off when a clever kick through from Ioan Lloyd set up an attacking platform five metres out which led to a first home try.
The forwards pounded away to within inches of the whitewash, before a miss pass from scrum-half Gareth Davies allowed Wales international Ellis Mee to dive over in the corner. Lloyd converted from the touchline.
The Scarlets, though, found themselves down to 14 men on the stroke of half-time when prop Alec Hepburn was yellow carded for an illegal no-arms tackle. Stormers fly-half Sascha Feinberg-Mngomezulu landed the simple penalty to make it 15-7 at the break.
However, the 14 men rallied strongly after the break and struck with a well-worked second try on 47 minutes.
A strong driving maul set up the opportunity, then impressive hooker Marnus van der Merwe drove into the heart of the Stormers defence. The ball was recycled quickly and Ioan Nicholas hit a great line to touch down at the posts for his second try in as many games.
The pendulum seemed to be swinging the Scarlets way, with the crowd in great voice.
However, that was punctured when from a clever line-out move saw wing Leolin Zas slice through to the posts unopposed for a converted score.
Back came the Scarlets with a Lloyd penalty to reduce the arrears to five points, then in the closing exchanges, Hughes threatened to produce a moment of magic with a snipe from a ruck.
However, Boks star Warrick Gelant managed to get back to win the turnover penalty and with that, the chance was lost.
Then, in the dying moments, replacement hooker Andre-Hugo Venter powered over to secure the victory to deny the Scarlets a losing bonus point.
Dwayne Peel’s side will now brush themselves own and turn their attention to Saturday’s West Wales derby against the Ospreys in Llanelli as the race for the top eight continues to hot up.
Scarlets – tries: E. Mee, I. Nicholas. Cons: I. Lloyd (2). Pen: Lloyd
Stormers – tries: B. Loader, D. Fourie, L. Zas, A. Venter. Cons: S. Feinberg-Mngomezulu (3). Pen: Feinberg-Mngomezulu
Att: 5,783