In Division Three both Pontypool United and Abergavenny are pulling off surprises in the East and they could continue as the United are at Brynithel and Abergavenny travel to the Civil Service Ground to meet Newport Saracens while Senghenydd face the useful Newport HSOB side.
In the West, unbeaten Kidwelly and Haverfordwest look set to carry on, but Pontyberem have a hard task at Tenby, while in the South-West the big match is at Bryncoch where Maesteg Quins must provide strong opposition, having slipped to third recently. The South-East will see a tight match at Gilfach Goch, who entertain Mountain Ash, but the big game is at Rhydyfelin, where unbeaten leaders Treherbert will have a tough task.
In Division Four East leaders Bargoed are at home to in-form Chepstow and Blaina entertain Monmouth, as the Saints of Peter's and Joseph's have a derby match in Cardiff.
West's best matches could be between Pembroke Dock Quins at home to Llandybie or top club Loughor against Neyland.
Penarth provide interesting opponents at Pontyclun in the South East and Pontycymmer will have to be at their best to win at Dowlais. In the South-West, the leaders look to have safe matches with a mid-table game between Centenary-celebrating Amman United and Morriston looks the closest call.
Four North will see a really hard match for Bala, without a win, as they visit unbeaten Ruthin and Nant Conwy are at home to Llandudno with Mold at home to mid-table club Llangefni.
There is no programme in Division Five East this weekend, though in the West, leaders Cefneithin face a hard struggle against third-placed Aberaeron, while Crymych in second will entertain Pontyates.
South East leaders Llantwit Major will do well to hang on at Llandaff North and Llandaff, just a point off the top, face a hard match away to Bridgend Sports Club. There are interesting matches in the lower regions as Deri entertain Ogmore Vale and Ferndale take on Rhiwbina.
In the South West, unbeaten Resolven face a tricky game at Porthcawl , but the best match could be at Crynant, where second-placed Aberavon Green Stars provide the opposition.
Five North will see the students of Bangor University facing their hardest match, away to leaders Denbigh, while unbeaten Colwyn Bay face Rhos and Llanidloes hope to push Bethesda all the way.