Clinging to a three-point lead, but under the cosh for most of the second half, the holders looked out on their feet until James Hume’s late, late breakaway touchdown to secure an ultimately flattering ‘Inst’ win.
Campbell may rue the absence of a reliable place-kicker as it spurned a plethora of second-half penalty chances, opting instead for position or incessant waves of forward drives.
‘Inst’ overwhelmed Campbell in the opening moments, a sweeping three-quarter attack and clever drive by prop John Dickson drawing a straightforward third-minute penalty kicked by centre James Hume.
Campbell scrambled back into the game, No.8 Jack Barry-Glendinning prominent and forced a 22nd-minute penalty well converted by flanker John Crowther to level matters.
But right on half-time ‘Inst’ edged ahead again when Hume landed a monstrous penalty after some more enterprising build-up play for a 6-3 lead.
On the restart it was Campbell which turned to free-running attack, Inst relying on its well-organised defence to keep its city rivals at bay. John Crowther was just awry with a 50th-minute penalty as Campbell dominated territory and possession.
On a rare breakaway winger Mark Keane took on the Campbell defence in the 55th-minute with a kick-and-chase, only to be surprisingly ‘sin-binned’ for an alleged high tackle.
Injuries and cramp meant the second period was littered with stoppages and replacements, but the contest was always compelling and hugely athletic.
In the very last minute, as Campbell looked the more assured and more likely winners, Inst centre Hume gambled, completed the intercept and raced 70 metres for a try at the posts which he improved with the last kick of an enthralling decider.
RBAI: J Finnegan; C Field ©, J Hume, B McGavock, M Keane; M Lowry, R O’Donnell; C Reid, N Saulters, J Dickson; H Gallagher, P McLernon; C Fryers, C Cloke, D Whitten.
Replacements: B Gribben, J Chambers, C Barrett, B Robinson, Y Omar, N Armstrong, D Lyttle, Z Davidson.
CAMPBELL COLEGE: B Webb; J Savage, J Haldane, N Koplewsky, J Howard; P Beverland, M Corry; M Russell, J Boyle ©, T O’Toole; J Nelson, M Crowther; J Macartney, J Crowther, J Barry-Glendinning
Replacements: J Chambers, J Clarke, J McKee, M Robinson, T Brady, R Cahoon, O Yandall, R Meharg.
Referee: S Gaffikan