Cardiff Blues completed the double over the Scarlets in a tight Guinness PRO14 contest at Parc y Scarlets.

The home side threatened a second-half comeback when Scotland international Blade Thomson crossed with 12 minutes remaining.

But for the second successive game, Blues finished the match the stronger to secure the spoils.

The Scarlets will rue not turning pressure into points after enjoying the better of territory and possession.

But they found a resolute Blues defensive wall tough to break down.

The Scarlets brought back Wales internationals Wyn Jones, Jake Ball, Ryan Elias and Johnny McNicholl into their starting line-up, while there was the welcome sight of Ken Owens back in the match-day 23; the hooker having recovered from shoulder surgery.

The home side started the match with plenty of endeavour and were on the front foot early.

No. 8 Sione Kalamafoni went close from a short-range line-out catch and drive, but the Scarlets couldn’t secure another line-out and the Blues were able to clear their lines.

In contrast, the visitors capitalised on their first period of pressure inside the Scarlets 22. Fly-half Jarrod Evans - the tormentor-in-chief two weeks ago - produced a lovely off-load to send full-back Matthew Morgan through the gap for a try that Evans himself converted.

As the Scarlets looked for a response, a deft kick through from Dan Jones bounced into the path of Johnny McNicholl, but his pass couldn’t find Steff Evans on his outside and the chance was gone.

More Blues pressure led to three points from the boot of Evans to extend the visitors’ lead to 10-0 and that was how it stayed until the break.

The Scarlets started the second-half in determined fashion, enjoying the bulk of territory and possession.

But for all their chances close to the line, they had to be content with a penalty from the boot of Leigh Halfpenny.

Club captain Owens entered the fray on 48 minutes, but the Scarlets then lost Wyn Jones and Kalamafoni to injury - Sione taking a blow to the head attempting to tackle the Blues’ Moldovan prop Dmitri Arhip.

Scarlets thought they had scored when Angus O’Brien pounced on a cross-field kick on 61 minutes, but the try was ruled out following consultation with the television match official, who adjudged there had been an illegal push just before.

The Scarlets finally opened their try account when replacement Steff Hughes put in a lovely chip into the path of Thomson, who gathered and crossed in the corner, and when Halfpenny converted from the touchline only three points were in the game.

But that was the Scarlets’ last chance.

Kieran Hardy was yellow carded in the closing moments and Blues saw out the match close to the Scarlets line.

The result sees the Blues leapfrog the Scarlets in the Conference B standings having played a match more.