Scarlets have recorded a 14-11 victory over the Cardiff Blues to maintain their position at the top of Conference B in the Guinness PRO14.
Wayne Pivac's side scored two tries courtesy of wing Tom Prydie and outside half Rhys Patchell, which were converted by Leigh Halfpenny.
Ellis Jenkins grabbed the Blues' only try on his first appearance of the season, after recovering from surgery to his hamstring, with Gareth Anscombe knocking over two first-half penalties.
The Blues opened the scoring with a penalty from Anscombe as a result of a powerful run from wing Tom James.
But it was the visitors who grabbed the first try of the game when Wales' youngest ever international Prydie touched down.
The Scarlets scrum obliterated the home eight allowing scrum-half Gareth Davies to find his way through the defensive line before offloading to the winger.
The Blues hit back with a score from replacement flanker Jenkins who powered his way over from short range following a powerful driving lineout from the hosts.
But on reflection Scarlets will feel hard done by as the replay showed the ball was grounded short.
The lively Davies had a try disallowed after openside flanker James Davies was deemed to have illegally kicked the ball out of the scrum.
And the Blues came close to extending their lead on the stroke of half-time with openside flanker Olly Robinson ankle tapped by Davies with no defenders in front of him. Davies' intervention meant the hosts led 11-7 at the interval.
Scarlets started the second half like a house on fire with former Arms Park favourite Patchell crossing after just five minutes with the try sparked by a surging run from openside flanker Davies.
Where the Blues pack held the upper hand in the first half, the Scarlets pack were far more aggressive in the contact area for the second 40 minutes.
Despite the dominance of the Scarlets scrum the hosts managed to get a foothold in the visitors' 22, with Matthew Rees crossing the whitewash only for the TMO to decide the ball was held up.
The Blues were given an opportunity to level the scores with five minutes to go but opted to go for the corner rather than kick a straightforward penalty.
The home side threw the kitchen sink at the hosts in the final stages of the game but the Scarlets defence held firm.