Llanharan have a tough task to stay at the top of One East when they travel to Virginia Park to take on a Caerphilly side only three points behind them in the table.
The Dairymen could be overtaken by Merthyr, who visit a Penallta outfit still smarting from their heavy defeat last week, or by Newbridge who entertain Rumney.
Bottom-placed clubs Newport Saracens and Ystrad Rhondda meet with the losers left stranded at the foot of the division.
Four clubs are making the pace in One West with leaders Carmarthen Quins hoping to maintain their three point advantage over Tonmawr by beating visitors Felinfoel. The high-scoring Tonmawr outfit, who have played a game less than Quins, play host to Bonymaen while Narberth travel to Maesteg.
The Otters have already bagged 23 tries in their four matches to date but cannot afford to slip as Whitland are unbeaten, only two points behind, and will relish the visit of Carmarthen Athletic who conceded 12 tries on their last away outing.
Treherbert will be looking for points in their trip to Fleur de Lys in Two East. After three matches they have yet to open their account while Fleur already have a victory in the bag. Leaders Llantrisant are at Abergavenny who have lost three times this season so the Black Army should remain in pole position.
Penclawdd have a tough trip to Builth Wells as the Two West leaders have won all four matches this season, but the Cocklemen have won away from home so will not be overawed at meeting the Bulls. There is a bottom-of-the-table clash at Pencoed where the home side entertain Gorseinon with only try count separating the teams.
Rhymney have a tough task in Three East when leaders Gwernyfed visit War Memorial Park. The Brewers have lost both opening matches conceding over 70 points while Gwernyfed are a point ahead at the top of the table. Nelson are handily placed to take advantage of any slip-up against Rhymney and they are home to a New Tredegar side with one bonus point keeping them off the bottom.
Pontyberem have gained maximum points from their first four matches and are already six points ahead of second-placed Cardigan in Three West. They take that record to Lampeter while Cardigan visit bottom club Llanybydder. Aberystwyth are also unbeaten but have played only three games. They entertain a Tumble side that were soundly beaten last time out.
Four clubs are within two points in Four East and it could be all change after the weekend. Leaders Llandaff take on the Squirrels of Rhiwbina in an all-Cardiff clash at Bishop's Field while Monmouth and Machen will hope to keep their unbeaten records against Crumlin and Tredegar Ironsides respectively.
Top plays bottom in Four West where leaders Brynamman play host to Cwmgors. Four clubs are on ten points and two of them, Trimsaran and Tycroes, play each other while Betws visit Tenby and Hendy are at unbeaten Llandeilo.
Abercarn are two points clear at the top of Five East and they entertain Blaenavon while Oakdale, three wins from three outings, put their unbeaten record on the line against Usk.
Swansea Uplands are without a point in Five West and they travel to Milford to play the Mariners who have won their opening three fixtures. Leaders Cefneithen play host to an Aberaeron side that recorded their first victory last weekend.
The Welsh Rugby Union is forming a new Youth Board with a brief to help keep more young people involved in the game during their late teenage years and beyond. The first task of the fifteen strong Board will be to analyse and consider the issues which lead to a number of youngsters drifting away from the sport between the ages of 16 and 21. To apply visit www.wru.wales/youthboard
The Foster's Challenge Cup will involve the 12 Principality Premiership sides and will run during European and British & Irish Cup weeks, providing vital fixtures for the participating clubs and an opportunity for upcoming players to step up to semi-professional rugby and make a claim for starting places within the Premiership squads.
Eighty schools and colleges in Wales now have a full time rugby officer as part of the WRU's school club hub scheme. All of the school club hub officers recently gathered at the National Centre of Excellence for various workshops.
With Liam Williams forced out of the World Cup through injury, lock Luke Charteris and Skills Coach Neil Jenkins say they have to put yesterday's defeat behind them as Wales now look ahead to another physical encounter against South Africa in the quarter-finals of the Rugby World Cup.
WRU Consultant Head of Physical Performance Paul Stridgeon praises the Physical Performance department for their work and dedication as he addresses the media ahead of Wales' Pool A clash against Australia
Twelve young people have been selected to follow a one year WRU Coach Core apprenticeship programme. Coach Core was set up by the Royal Foundation of the Duke and Duchess of Cambridge and Prince Harry as part of the Olympics legacy in 2012 and the Duke of Cambridge was on hand to meet the apprentices on their first day in the job. The programme has been funded by the Hunter Foundation.
The WRU has launched a campaign to create a long term legacy for Welsh club rugby by highlighting the advantages of volunteering. Rhian Edwards, a volunteer at Seven Sisters, has enjoyed many benefits of her volunteering at a grassroots rugby club including being part of the Rugby World Cup volunteer workforce after being nominated by the WRU - and the WRU is asking for more people to develop their 'Welsh rugby roots'.