Nicky Robinson's accuracy with the boot proved the difference between the two sides as Cardiff Blues clinched a 33-17 Celtic League win over Connacht at the Arms Park.
Cardiff Blues (23) 33
Tries: J Robinson, Macleod, Dewdney.
Cons: N Robinson (3). Pens: N Robinson (4).
Connacht (12) 17
Tries: McPhillips (2), O'Sullivan. Cons: Elwood.
The young fly-half kicked 18 points in an accomplished all-round display after both sides managed three tries apiece in an entertaining encounter.
Wales World Cup reject Jamie Robinson scored the pick of the Cardiff's tries, with fellow backs Nick Macleod and Dean Dewdney also contributing.
Connacht winger Connor McPhillips crossed twice, adding to John O'Sullivan's early opener.
Robinson brought an enthralling first-half to end with the third of his four penalties to stretch his side's lead to 23-12 at the interval.
His opening effort cut the visitors' early lead after Sullivan had burst through a huge midfield gap to score the game's first try.
The home side replied with an incisive three-quarter move which saw centre Macleod beat the Connacht defence to touchdown in the left corner.
But the visitors regained the lead 10 minutes later after McPhillips squeezed his way into the right corner to ground the ball with only inches to spare.
Jamie Robinson, omitted form Wales' World Cup squad, showed all his pace and strength to put the Blues ahead again with the best try of the half.
Brother Nicky kicked his second conversion and then a couple of penalties to give Cardiff some breathing space going into the second half.
The home side pilled on the pressure after the break, and their cause was greatly helped when referee Rob Dickson finally lost patience with constant Connacht infringements to send number eight Matt Lacey to the sin-bin.
It took the home side only a few minutes to make the numerical advantage pay when winger Dewdney crossed for Cardiff's third try.
Robinson's mercurial conversion form the touchline opened a 19 point lead with just over 20 minutes to go.
But any thoughts of relaxing and counting down the clock were quickly forgotten when the Irish province hit back almost immediately with their best try of the match.
Winger McPhillips showed the Cardiff defence a clean pair of heels to grab his second score, but veteran fly-half Eric Ellwood failed to add the extra points.
The try lifted Irish spirits and it became Cardiff's turn to defend desperately. The pressure led to Cardiff's Dan Baugh being sin-binned for killing the ball, but Connacht failed to make the most from the resulting penalty.
Cardiff actually came closest to scoring again when McPhillips was denied by a last ditch tackle in the corner, but the Blues had already done enough to ensure a clean sweep for Welsh sides over Irish opposition this weekend.
Cardiff Blues: Donavan van Vuuren; Nick Walne, Jamie Robinson, Nick Macleod, Dean Dewdney; Nick Robinson, Andrew Moore; Ken Fourie, Andrew Lewis (capt), Ben Evans, Dan McShane, Andy Moore, Rob Appleyard, James Malpas, Dan Baugh.
Replacements: John Yapp, Ryan Price, Chris Stamatakis, Nathan Thomas, Robin Sowden-Taylor, Richard Jones, Lee Abdul.
Connacht: Mark McHugh; Conor McPhillips, Darren Yapp, Tim Allnutt (capt), Wayne Munn; Eric Elwood, Chris Keane; Warren O'Kelly, Bernard Jackman, Adrian Clarke, Damian Browne, Andrew Farley, Michael Swift, John O'Sullivan, Matt Lacey.
Replacements: John Fogarty, Fabian Boiroux, Mike McCarthy, Mick Carroll, Conor O'Loughlin, David Hewitt, Ted Robinson.
Referee: Rob Dickson (Scotland).