Munster prevailed over Dragons' stiff challenge to overcome a three point deficit and secure a 16-20 win at the Rodney Parade stadium in Newport during the 2016-17 Pro12 clash on Saturday.
Robert Lyttle scored a double whereas Ruan Pienaar's try and a couple of conversions helped Ulster defeat the Dragons by 29 - 8 during the Pro12 encounter at Belfast on Friday.
Zebre concluded the ongoing Pro12 season on a winning note with a 47-22 triumph over Dragons to secure a qualification for the next year's European Champions Cup.
Montpellier set-up a championship clash with Harlequins ahead of next month's Challenge Cup final in Lyon after powering past the Dragons 22-12 at the Altrad Stadium.
Cardiff Blues maintained their hopes of qualifying European Champions Cup spot for next season with a comfortable Guinness PRO12 win over Dragons at the Arms Park.
Gloucester's up-and-down season continued as Newport Gwent Dragons pulled off a shock 23-21 victory at Kingsholm in the quarter-final of the European Challenge Cup.
Taulupe Faletau played his final game at Rodney Parade for Newport Gwent Dragons before a big-money summer move to Bath - but the Ospreys spoilt his farewell party with a 26-20 victory.
Angus O'Brien struck the post with a last-ditch drop-goal attempt as Newport Gwent Dragons fell to a 19-17 Guinness PRO12 loss to Treviso on Friday night.
Connacht came from behind to secure a bonus-point 26-21 victory away to Newport Gwent Dragons on Thursday night, a result that sees them move four points clear at the top of the Guiness Pro12.
A late Paddy Jackson penalty was to prove crucial as Ulster secured a late 17-15 win over Newport Gwent Dragons to send the Irish side top of the Guinness PRO12 table.
Sale mercilessly ripped top spot in Pool 2 and a home quarter-final in the European Challenge Cup away from Newport Gwent Dragons with a 38-5 bonus-point victory over the Welsh region at AJ Bell Stadium.