DOLPHIN 13 CORK CONSTITUTION 12, Musgrave Park
Scorers: Dolphin: Try: Penalty try; Con: Barry Keeshan; Pen: Barry Keeshan; Drop: Barry Keeshan
Cork Constitution: Tries: Tom Gleeson, Frank Cogan; Con: Richie Lane
Dolphin captain Barry Keeshan flicked a well-judged kick through the posts in the second minute of injury-time to wrestle back the league points for the home side.
This Musgrave Park clash was a real war of attrition in the first half, with the rain adding to the error count and scores proving very hard to come by.
Munster centre Tom Gleeson slipped through for a fifth minute try to open Cork Con's account. Richie Lane added the conversion.
The visitors scuppered their chances of building of their early lead by missing four penalty kicks at goal, including a second minute effort by Lane.
Keeshan replied for Dolphin with a tenth minute penalty and the home pack mustered a surge towards the end of the first half, gaining a penalty try decision from referee Alan Lewis - albeit with big back rower James Coughlan seemingly having crossed the whitewash.
The drive towards the line was made that bit easier for Dolphin by the fact that Cork Con had lost their influential lock Merle O'Connell to a yellow card.
Keeshan, who has a new half-back partner in former UCC captain Sam Cronin, added the simple conversion to give Dolphin a 10-7 lead to take into the break.
The second half burst into life when former Cork Con skipper Frank Cogan muscled his way over for the visitors' second try, which went unconverted.
Cogan made Dolphin pay for a lineout mishap close to their own line where they failed to control possession.
Brian Walsh's side looked like they might hold on for a famous win, but Keeshan denied them with a fine drop goal.
The victory was a hugely significant one for Dolphin, considering that they had never previously beaten their city foes in AIB League competition.
Dolphin coach Steve Ford told the Irish Examiner: "Funnily enough, we did discuss what we might try to do if we were within a point or two coming to the end, but nobody could kick it for Barry - he had to do that himself and he did it brilliantly.
"It's going to be a very intense and very closely-fought league so it's important to get a good start and it's crucial at any rate to win our home games.
"I was very pleased with many aspects of the performance, but I recognise there are areas for improvement."
DOLPHIN: Denis McCarthy; Niall O'Driscoll, Danny Barnes, Eric Moloney, Paul Hurley; Barry Keeshan (capt), Sam Cronin; Dave Ryan, David Nathan, Christy Condon, Chris Rowe, Kyle O'Dwyer, Robbie Allen, Barry O'Mahony, James Coughlan.
Replacements used: Fraser Stone for O'Dwyer (23 mins), Rory Kenneally for McCarthy, Julien Brugnaut for Ryan (both 57), Stephen Cotter for Nathan (70), Cormac O'Flynn for Barnes (78), Ryan for Condon (79).
CORK CONSTITUTION: Daragh Lyons; Richie Lane, Tom Gleeson, Evan Ryan (capt), Cronan Healy; Scott Deasy, Duncan Williams; Stephen Archer, Robert Quinn, Martin Gately, Merle O'Connell, Billy Holland, Peter O'Mahony, Ed Leamy, Frank Cogan.
Replacements used: Darragh Hurley for Gately (39 mins), Brian Hayes for Cogan (45), Simon Zebo for Healy (65), Alex Ryan for O'Mahony (78).
Referee: Alan Lewis (IRFU)