DOLPHIN 16 CLONTARF 10, Musgrave Park
Scorers: Dolphin: Try: Barry O'Mahony; Con: Barry Keeshan; Pens: Barry Keeshan 2; Drop: Barry Keeshan
Clontarf: Try: Phil Howard; Con: Daragh O'Shea; Pen: Daragh O'Shea
Clontarf remain top of the Division One table but their lead has been cut to just two points ahead of the Christmas break.
Dolphin, who are now right in the play-off hunt in fourth position, fielded an enviable back row unit of Munster duo Justin Melck and James Coughlan and young openside Barry O'Mahony.
South African Melck was making his debut for the club at number 6, while Coughlan slotted in once again at number 8 after a late cameo against Clermont Auvergne on Saturday afternoon.
A first-minute indiscretion allowed out-half Barry Keeshan slot a penalty and nudge wind-backed Dolphin ahead.
The Cork men led 9-3 at half-time, with Keeshan adding another penalty and a drop goal to his side's tally, although he did miss two other penalty attempts and on the balance of play, the hosts should really have been further ahead.
They made heavy weather of things and a number of knock-ons spoilt attacking moves when the 'Tarf defence looked stretched.
Team captain Daragh O'Shea kicked a penalty for the north Dubliners' only points of the first half.
Then in the 55th-minute, Dolphin strengthened their grip on the game with a converted try.
Coughlan was central to it. He picked off a lineout inside the 'Tarf 22, drove on and then O'Mahony popped up on his shoulder to take a pass and crash over the try line.
Keeshan added the conversion but the league leaders set up a tension-filled finish when their full-back Phil Howard darted over for a fine, individual try in the 74th minute.
He collected a high ball on the ten-metre line and broke a series of tackles before crossing in from the right and in behind the posts, making O'Shea's conversion all the easier.
However, 'Tarf's revival came too late and Dolphin determinedly hung on to take all four points and extend their impressive unbeaten home record in the league to 11 matches.
Indeed, the Cork club have not lost a league game at Musgrave Park since March 2007 and the last non-Munster side to beat them there was Clontarf two years ago.