North sprung off the bench for the final ten minutes while Davies had already been on as early as the 32nd minute when Scott Williams, who scored the winning Six Nations try over England at Twickenham last month, had to go off.
It was Andy Fenby’s double that the did the damage on the scoresheet but there were also impressive performances from Wales hookers Ken Owens and Matthew Rees while Gareth Davies and Dominic Day also crossed to seal the bonus point 26-14 victory.
Wales wing Alex Cuthbert – scorer of Warren Gatland’s side’s only try against France earlier this month – did touch down for the Blues, as did Casey Laulala, but it is the Scarlets who are now homing in on a play-off place, one point behind fourth-placed Glasgow Warriors, while Cardiff are a further five adrift.
Elsewhere, Munster regained second spot and closed the gap at the top of the table to eight points – capitalising on Leinster’s shock defeat on Friday – with a well-earned 20-16 win over Connacht.
Simon Zebo again gave the Ireland selectors a timely reminder of his finishing qualities, bursting through the Connacht defence to level things up at 13-13 with 20 minutes to go.
Miah Nikora, who finished with 11 points, kicked Connacht back in front only for flanker Tommy O’Donnell’s 67th-minute try to seal Munster’s win.
And in the other match of the day, Ian Whitten’s last-gasp try handed Ulster a 27-23 win against Treviso and keeps their play-off hopes alive.
Treviso had looked set to complete a double over Brian McLaughlin’s men as they led 23-20 in the closing stages.
Earlier, Enrico Ceccato’s opening try had boosted Treviso but second row Chris Henry touched down for Ulster.
A try by Alberto di Bernardo in the 69th minute rocked Ulster but they got the win with Whitten’s last-gasp score.
© Sportsbeat 2012
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BIOGRAPHY: Anthony Martial