Rhys Webb's try-double raised his tally for the season to 11 and sent Ospreys back to the top of the GUINNESS PRO12 table as they defeated Ulster 31-20 at the Liberty Stadium.
Dan Biggar and Hanno Dirksen also went over to secure a four-try bonus point, and an eighth straight league win at home, ensuring Tommy Bowe and Rob Herring's late scores were little more than consolation.
The result sees Ulster drop out of the top four but Glasgow Warriors are up to second after a second-half comeback saw the Scottish side beat Munster 21-18.
The first half was bookended by close-range tries from JJ Hanrahan and Robin Copeland to hand the Munstermen an 18-9 lead.
But Glasgow's second-row stepped up after the break as first Leone Nakarawa and then Jonny Gray crossed the whitewash to stretch their winning run at Scotstoun to 13 league games.
The loss means Munster now lie third in the table while the final play-off spot is occupied by their arch-rivals Leinster, who rode a late try from winger Zane Kirchner to a 21-11 victory over Connacht.
Shane Jennings and Connacht's George Naoupu had earlier traded tries to leave the game finely poised going into the final stages before Kirchner capitalised on sloppy defending to seal the win.
While Leinster were made to work hard at the RDS Arena, Edinburgh had an easier ride when they hosted winless Benetton Treviso - Sam Hidalgo-Clyne scoring the pick of six tries in their 48-0 triumph.
Mike Coman, WP Nel, Grayson Hart, Roddy Grant and Dave Denton also dotted down in a game marred by Romulo Acosta of Treviso's straight red card for punching.
Treviso's fellow countrymen Zebre fared a little better but still came away pointless from Rodney Parade as they went down 25-11 to Newport Gwent Dragons.
Ross Wardle, Hallam Amos and Rynard Landman all crossed for the Dragons while Zebre's sole try came from the unlikely source of hooker Andrea Manici.
And Josh Navidi was the star of the show as his two first-half tries saw Cardiff Blues pick up a third league win of the season by defeating Scarlets 21-9 at BT Sport Cardiff Arms Park.
TRY OF THE WEEKEND
Treviso offered little resistance to the Edinburgh juggernaut at BT Murrayfield and there was less than a minute on the clock when scrum-half Sam Hidalgo-Clyne opened the scoring in spectacular style.
Joe Carlisle's clearance failed to find touch around halfway and some neat interplay between Jack Cuthbert and Greig Tonks created space for Hidalgo-Clyne to race over.
BREAK OF THE WEEKEND
Alun Wyn Jones is not necessarily a man you expect to scythe through a defensive line but the veteran lock did just that to get the ball rolling in Ospreys' win over Ulster.
Jones sidestepped one tackle and drew in a second defender before offloading to prop Marc Thomas who released Dan Biggar for the game's opening try.
PLAY OF THE WEEKEND
Newport Gwent Dragons had just one league win coming into the weekend's action but a team try, finished by Ross Wardle, set them on course for a second victory against Zebre.
The ball was collected on the halfway line and worked to Tom Prydie, who drew in a number of defenders before passing to Wardle - the centre cutting inside some more Zebre players to dive over.
PLAYER OF THE WEEKEND
Josh Navidi capped off his impressive all-round performance with two tries in Cardiff Blues' hard-fought win over Scarlets.
The No.8 marshalled a scrum and a driving maul towards the Scarlets try-line before burrowing his way over on both occasions and even a late sin-binning couldn't take the sheen off his display.
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