The action kicks off with Ulster, a point behind leaders Munster, facing The Ospreys at Ravenhill. The Ulstermen have won their last 11 games at home and have lost only once in the Celtic League this season, while The Ospreys have had a wretched start to their title defence. Form would suggest that should Munster slip up in Cardiff then Ulster could go top.
However that Munster trip to the Blues could see the Irish side maintain their fine early season start - but to do that they will need to break their duck at the Arms Park where they have lost four times in the past.
Also on Friday Connacht face the Glasgow Warriors with both sides struggling to find some form in the league. Although the Irish province achieved back to back wins in the European Challenge Cup they are looking to halt a run in the Celtic League which has seen them slip to six successive defeats, while the Warriors have not won any of their last five games.
Sunday's first game sees Leinster return to Donnybrook after two games at the RDS to face Edinburgh Gunners who, despite their high league position, have failed to click away from Murrayfield. A win will see the home side leapfrog the Gunners as both sit on 22 points in third and fourth place respectively.
The round ends with Border Reivers travelling to Newport-Gwent Dragons. Despite occupying fifth place, six points ahead of the Dragons, the Border's team has never won in Wales and the Dragons will be looking to kick start their campaign in what is remarkably only their second home game of the season in the Celtic League.
A special video package as Pontypridd claimed the double for the first time in their history by winning the Principality Premiership final, including match build-up, highlights, post match reaction and dressing room celebrations.