Friday night sees Leinster travel to Rodney Parade to face the Dragons - and the Irish side will not only be looking to keep the momentum going after their six try defeat of the Borders last weekend but also will have half an eye on top spot should the Ospreys slip up on Saturday.
However the Dragons have a proud home record, and will give Leinster a much stiffer examination than they faced last Friday against the Borders.
Dai Young was pleased with the Cardiff Blues' performance in their win over Connacht at the Arms Park last weekend -but will want to replicate that home form on the road when they travel to Edinburgh. The Cardiff side do not have a great record in Scotland but should view this game as a chance to put it right against an Edinburgh Rugby side who are still without Scott Murray - and also without a win this season.
The Borders, who are also still to record a win this term, have to travel to Ireland for a second consecutive week, this time to face Connacht. After their mauling in Dublin last week they will be looking for some more encouraging signs against a Connacht team who have had an erratic start to their season.
Their opening win against Glasgow was heartening, but since then they have lost at home to Ulster and last week in Cardiff to the Blues. The signs for The Borders are not optimistic however, as they have yet to record an away win in Celtic League rugby.
The leaders - The Ospreys - are also in action on Saturday and will be looking to maintain their proud record of not conceding a league point in any of their four games so far this season.
They showed real grit to battle back from a 14 point deficit against Ulster last weekend, but Glasgow will be hoping to replicate the strong defensive performance that saw them battle hard for their wins over Edinburgh Rugby and the Borders.
The final game of the round is on Sunday - and what a game it promises to be. The defending champions, The Scarlets, have finally stirred into life with their win over Edinburgh last week and now travel to one of the toughest of venues in Europe for visiting sides - Thomond Park, Limerick.
Munster will be well rested after their bye week and will be keen to record their first win of this season's competition against the Scarlets. However the Welshmen will only need to look back to last season for inspiration - when they ended Munster's six year winning streak at the ground with a 19-12 victory.