In a disappointing game Scarlets showed how to take the few tryscoring chances that came along. Flanker Aaron Shingler grabbed the opening try after Glasgow lost possession in their own half. The second came on half-time, scored by winger Andy Fenby, again following lost Glasgow possession.
The third was scored by winger George North after good play by his backs colleagues. The home side's points came from two penalties in the first half from Ruaridh Jackson and a try near the end from Chris Cusiter, converted by Duncan Weir.
Eric Elwood's Connacht rebounded from last week's defeat to Cardiff Blues with a commanding 30-17 win over Zebre in Italy.
Miah Nikora led the charge for the Irish side with a 13th-minute penalty to put his side in front and after the opening try from Tiernan O'Halloran, Nikora followed up with the conversion and a second penalty. Leading 13-0 at half-time, Connacht saw their lead reduced by a converted try from Samuele Pace early in the second half, but a Nikora penalty soon settled nerves.
George Naoupu squeezed over with Connacht's second try but Zebre's Andries Van Schalkwyk scored an impressive try which was converted by Luciano Orquera to give the hosts a glimmer of hope. That hope was brought to an end when Mike McCarthy crossed over and Nikora rounded off a fine night with his sixth successful kick from six attempts.
Munster handed new head coach Rob Penney his first Thomond Park win as they notched a 19-6 victory over Benetton Treviso.
Team captain Doug Howlett dashed through for a fifth minute try, in response to Alberto di Bernado's opening penalty, and Munster foraged into a 16-3 lead by the break.
But that proved to be the only try of the game with Ian Keatley, who finished with 14 points, and di Bernardo kicking a penalty apiece in the second half.
Greig Laidlaw coolly slotted a drop goal from in front of the posts to give Edinburgh a 21-19 win on the night Cardiff Blues returned to Cardiff Arms Park.
The hosts seemed certain to celebrate their return to the ground with victory when Leigh Halfpenny's fourth penalty put the Blues 19-11 ahead, following Alex Cuthbert's try.
But a converted penalty try pulled the deficit back to a single point, and after Cardiff had missed two chances to stretch their lead, Scotland outside-half Laidlaw ensured Edinburgh bounced back from last week's defeat to Munster in dramatic fashion. Tim Visser went over for Edinburgh's other try.