All three Magners League sides won through in their final games before next weekend's crucial Heineken quarter-finals.
Munster gained the win they expected at Connacht's Galway Sportsground, but it was not plain sailing as they were forced to show their fighting spirit to come from behind and eventually run in 15-6 winners.
They now sit second on the Magners League table, behind leaders Leinster who play the Scarlets on Saturday evening.
But it was the Welsh sides that really impressed on Friday.
David Young's Cardiff Blues travelled to Scotland to face a resurgent Edinburgh under the coaching of former England boss Andy Robinson.
And, riding on the back of grand Slam fever, the Cardiff side nilled their hosts with a 20-0 victory that will inspire confidence for the trip to Toulouse next weekend.
Two Tom James tries helped the Blues to a convincing victory at Murrayfield that allowed the Welsh side to leapfrog Edinburgh in the Magners League.
The Scottish side withstood pressure from the Cardiff visitors until Ben Blair's penalty after 19 minutes.
But James went over for a try, converted by Blair, and fellow winger Jamie Roberts went over the whitewash a second time before the break. Second-half home pressure failed to produce points and James added a try.
The Ospreys are also looking in fine form. Fresh from qualification to the EDF Energy Cup final, they brushed aside Ulster at the Liberty Stadium, running in convincing 32-7 winners.
Confidence is as high as the skills levels at the moment, and it will take a monumental effort from Alan Gaffney's side to derail the Ospreys bandwagon next weekend.
