Connacht (8) 17
Try: Murphy Pens: Keatley 4
Scarlets (3) 13
Try: Maule Con: Newton Pens: Newton 2
Frank Murphy prepares to score a try despite the arrention of Daniel Evans
The Scarlets' hopes of securing a top- four play-off place in the Magners League suffered a setback with this defeat away to Connacht.
Frank Murphy scored a try and then Dan Newton and Ian Keatley traded penalties to leave the score 8-3 at half-time.
A Gareth Maule try, converted by Dan Newton, nudged Scarlets 10-8 ahead but three penalties from Keatley saw Connacht move seven points clear.
Newton scored another penalty and Scarlets ensured a bonus point.
Connacht outfought the Scarlets at the Sportsground to earn their first Magners League win since mid-September.
Half-backs Keatley and Murphy scored all of Connacht's points, with Murphy's 13th-minute try leaving the Scarlets 8-3 adrift at the break.
Maule touched down from the visitors' first attack of the second half.
But the Welsh region could only garner a losing bonus point as Keatley, with a 12-point tally, booted Connacht home.
A gusting wind was the main factor in a disjointed opening 40 minutes.
Good early work from Connacht's forwards went unrewarded when Keatley scuffed a long-range penalty away to the left of the posts.
The Scarlets pack kept the ball well, facing into the elements, but lacked the territory to put Connacht under serious pressure.
The returning Lou Reed, Rob McCusker and Johnathan Edwards were hungry for work and kept forcing tackles from the hosts, for whom stand-in captain Johnny O'Connor led by example.
In the 13th minute, Murphy linked with Keatley to the right of a scrum in the Scarlets 22.
He took the return pass and dummied past Regan King and Martin Roberts to score in the corner.
Keatley's missed conversion was followed by Dan Newton's opening penalty, six minutes later.
The young out-half slotted over from in front of the posts after a ruck infringement from Mike McCarthy.
The remainder of the half was slugged out between the packs - there was plenty of industry but no end product.
However, in injury-time, some good harrying from Murphy and Mike McComish forced the Scarlets to cough up a penalty, and Keatley fired over from outside the 22 for an 8-3 advantage.
The second half was just 54 seconds old when King evaded the grasp of the Connacht cover and passed for winger Maule to glide in at the left corner.
Newton tagged on the tricky conversion and the game suddenly went up a gear.
The Scarlets lost their way though, failing foul of referee Andrew McMenemy at the breakdown.
Keatley mopped up with two successful penalties from three attempts on goal, with the wind dying down.
On the hour mark, the Welsh side also had centre Scott Williams sin-binned for being offside at a Connacht ruck near halfway.
Connacht could not add to their try count, Michael Swift blew their best chance out wide when fumbling a pass from Troy Nathan.
Eric Elwood's men tightened their grip on the match points when Keatley added his fourth penalty, before Newton replied to give the Scarlets something to show for their efforts.
Connacht: Gavin Duffy; Brian Tuohy, Niva Ta'auso, Troy Nathan, Fionn Carr; Ian Keatley, Frank Murphy; Brett Wilkinson, Adrian Flavin, Jamie Hagan, Michael Swift, Mike McCarthy, Andrew Browne, Johnny O'Connor (capt), Mike McComish.
Replacements: Rodney Ah You for Hagan (42), Bernie Upton, Ray Ofisa for McComish (41).
Not used: Dermot Murphy, Dylan Rogers, Bernie Upton, Cillian Willis, Mia Nikora, Shane Monahan.
Scarlets: Daniel Evans; Darren Daniel, Regan King, Scott Williams, Gareth Maule; Dan Newton, Martin Roberts; Iestyn Thomas (capt), Emyr Phillips, Rhys Thomas, Vernon Cooper, Lou Reed, Rob McCusker, Johnathan Edwards, Ben Morgan.
Replacements: Rhys Lawrence for Phillips (66), Simon Gardiner for R Thomas (60), Jonny Fa'amatuainu for Cooper (66), Nick Cudd for J Edwards (60), Gareth Davies for Roberts (66)
Not used: O Evans, O Williams, Reynolds