Ashley Beck and Aisea Natoga grabbed first-half tries in a 17-12 Welsh derby victory for Ospreys as a fine defensive display at Liberty Stadium kept Scarlets away from the whitewash. Wales international Beck hit first while Natoga dotted down in first-half injury time – just after Rhys Priestland’s first penalty and Scarlets’ first score of the match. Priestland added another three penalties in the second half but Dan Biggar mustered seven points from the tee in total to keep any hopes of a Scarlets comeback at bay. Ospreys are something of a bogey side for Scarlets, who have won just one of their last 11 encounters with Steve Tandy’s men. The visitors were also looking to turn the tide on a five-game losing streak in all competitions – and were close to getting off to the perfect start. After winning turnover ball and a penalty, Priestland decided to go for the sticks but failed to hit the target. Then Scarlets flanker Josh Turnbull found the turf rather than a man with his pass and Ben John almost took full advantage, punting the loose ball ahead of him before running out of room to dot the ball down. Bruising tackles forced Ospreys to cough up the ball before they could truly get going for the first quarter-hour – but then the hosts’ backs truly sprang to life. Rhys Webb snuck his way through the Scarlets line to spark a tremendous break and despite being hauled down inches away from the try-line, Beck scooped up the ball to cross the whitewash before Dan Biggar added the extras. For all of Ospreys’ attacking intent it was Scott Williams who was leading the charge for the visitors and he was unlucky not to force a score after a breakaway of his own. Finally Scarlets got on the board through a Priestland penalty to seemingly take the initiative going into the break – but the hosts found time to hit again. After working the ball upfield Ospreys were knocking on the door under the posts before Sam Davies at full-back found Natoga – who found acres of space to touch down, with Biggar converting. The hosts were penalised near halfway early on in the second half and while Priestland’s explosive kick had the distance, it lacked the accuracy by just missing left. However Biggar was having no such problems and when presented with his own opportunity drilled through once more. Both fly-halves are battling for a Wales jersey and Priestland was able to get a counter-punch in by booting between the posts to give Scarlets a glimmer of hope approaching the final 20 minutes. And he continued to chip away at Ospreys’ lead with another finely-struck kick, as Scarlets started to sense hope. The momentum was with Simon Easterby’s side but the hosts continued to repel incoming attacks – before shooting themselves in the own foot as Natoga deliberately knocked on to earn a yellow card. But Ospreys’ resistance was no less impressive with 14 men and despite one more Priestland penalty, they held firm to clinch the Welsh bragging rights and reaffirm their hopes of a RaboDirect PRO12 play-off spot. Follow us on Facebook, join the conversation on Twitter, sign up to our YouTube channel for extensive match highlights and sign up to our newsletter for regular updates on the RaboDirect PRO12