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.
Wales reached their first semi-final since 2013 in the opening round of this season's HSBC World Rugby Sevens Series in Dubai. WRU TV's Graeme Gillespie recaps on what proved to be an eventful tournament
Wales and Ospreys back row James King, who came through the North Wales age grade system, nominated North Wales Regional Community Rugby Manager Marc Roberts, in the WRU's 'Diolch' initiative where squad players thanked those who played a part in their rise to the top.
Beating Merthyr has boosted Carmarthen Quins hopes of reaching a top eight spot in the Principality Premiership. Quins captain Haydn Pugh is delighted with his team's progress and is determined that everyone from the Under 6s through to the senior team, enjoys the ride.
When the Wales squad were asked to nominate individuals who played a big part in their early playing days, Wales and Dragons full back and wing Hallam Amos thought of his former Monmouth School rugby coach John Bevan.
Sam Cross and Luke Treharne have been named as co-captains of the Wales Sevens side as head coach Gareth Williams names his 12-man squad to play in the first leg of the HSBC World Series in Dubai next weekend.
Bedwas head coach Steve Law and players Nicky Griffiths and Alun Rees extol the virtues of the close knit club as they prepare to host third place RGC 1404 - who are one place head of them on the Principality Premiership points table - on Saturday.
Many of the Wales squad have said Diolch (thank you) to someone who played an important part in their early playing days by nominating them to be invited to the Wales v South Africa match. One person, Gowerton Comprehensive geography teacher Mr Dean Mason was nominated by two of his former pupils, Dan Biggar and Sam Davies.
The second WRU disability rugby pilot has been delivered, this time in Caerphilly schools, culminating in a festival at the Caerphilly Centre of Sporting Excellence, Ystrad Mynach tomorrow. Plans are in place to set up a Disability Rugby Club in Newbridge to provide long-term playing opportunities.
WRU TV: Hear from inside the Wales camp as Neil Jenkins discusses this weekend's clash with South Africa and how the squad are looking to put in a strong performance to round of the 2016 Under Armour Series