A first-half blitz saw Glasgow Warriors climb back to the top of the GUINNESS PRO12 table as they downed Zebre 26-5 at Scotstoun.
DTH van der Merwe crossed the whitewash twice while Chris Fusaro and hooker Kevin Bryce also dotted down as Glasgow wrapped up the bonus point before half-time.
To their credit, Zebre responded in the second period and scored the only points of the half as Dion Berryman got on the end of a grubber kick but that failed to spark a miracle comeback for the Italians.
The Warriors replace Munster as the GUINNESS PRO12 leaders after Anthony Foley's men suffered a 26-12 defeat to Ospreys at the Liberty Stadium.
Fly-half Sam Davies kicked 21 points and his long, lofted pass also freed No.8 Dan Baker to score the Ospreys' only try as the Welsh side moved up to fourth in the league - Donnacha Ryan and Keith Earls' late scores for Munster proving little more than consolation.
It was Leinster who were leapfrogged for the final play-off spot by Steve Tandy's troops as the Irish province failed to end Scarlets' 15-month unbeaten home streak at Parc y Scarlets.
John Barclay and Ben Te'o exchanged tries as the game was finely poised at half-time but Regan King slipped Jordan Williams in for try number two and Rory Pitman barrelled his way through Jimmy Gopperth for a third as the Welsh side triumphed 23-13.
And Ulster ensured that the only top-four team coming into the weekend who won were Glasgow as they suffered a 26-22 defeat at the hands of Newport Gwent Dragons in Newport.
Ulster had won their four previous GUINNESS PRO12 games but that run of form came to a crashing halt as three second-half tries for the tenth-placed Dragons meant Neil Doak's men had to settle for a losing bonus point.
Craig Gilroy crossed for the visitors before the break after good work from Rory Scholes but Jonathan Evans, Rhys Buckley and Dorian Jones secured the win despite Gilroy's second and Ross Adair set up a tense finale.
Meanwhile, Rhys Patchell's last-gasp conversion following Joaquin Tuculet's try helped ninth-placed Cardiff Blues to an enthralling 18-17 win over Connacht underneath the Friday night lights at BT Sport Cardiff Arms Park.
And Matt Scott's try double dealt Treviso just a second home league loss since October 10 as Edinburgh came out on top 29-8 at Stadio Monigo - Simone Ragusi's strip tackle and score the lone highlight for the Italian outfit.
TRY OF THE WEEKEND
Newport Gwent Dragons held a narrow 21-15 lead over in-form Ulster when they produced a fantastic team try to seal the victory with just seven minutes remaining.
After working the ball through the hands, winger Hallam Amos turned on the gas - sidestepping one defender and handing off Ruan Pienaar before slipping the ball to Carl Meyer to race over for the score.
BREAK OF THE WEEKEND
Hookers aren't normally renowned for their evasive running but Glasgow Warriors' Kevin Bryce proved he had the skills to match any back by slicing through the Zebre defence in his side's 26-5 win.
The 26-year-old received the ball just outside the Italians' 22 and picked the perfect line through the Zebre backline before holding off a last-ditch defender to dot down.
PLAY OF THE WEEKEND
At 34 years old, Regan King might not be quite as sprightly as he once was but the veteran Kiwi proved his handling skills are undiminished by creating the Scarlets' second try in their win over Leinster.
With the game finely poised at 10-8 to the Irish side, Scarlets went through 16 phases, worked the ball wide to King and the centre drew in two defenders before slipping the ball out of the back of his hand to an onrushing Jordan Williams for the pivotal try.
PLAYER OF THE WEEKEND
Glasgow's DTH van der Merwe grabbed a pair of tries in their win over Zebre as did Joaquin Tuculet in Cardiff Blues' narrow victory over Connacht but the performance of the weekend belongs to Ospreys' Sam Davies.
The fly-half kept his cool to kick 21 points and produced a long, raking pass to set up Dan Baker's try as the Welshmen climbed back into the GUINNESS PRO12 top four with victory over Munster.
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