UCD manager Nicky English paid tribute to two "really, really honest and earnest sides who fought it out tooth and nail".
"I don't know was it a Fizgibbon classic, but it was a classic Fitzgibbon
‘It was a fantastic game in the worst of conditions, hard-fought by two honest, earnest sides. You have to fight every ball to the last, it’s a brilliant competition. I really enjoyed tonight’.
The crucial breakthrough for UCD came when Colm Cronin goaled in the 75th minute to open a 1-17 to 1-13 lead.
The game ebbed and flowed in normal time, UCD building up an 0-7 to 0-1 lead before a Jack Fagan goal from Carlow on the half hour brought them right back into contention with wind advantage to come.
Carlow went two points clear in the second half but UCD refused to buckle and defiant hurling from the likes of Pat Hannon, Cian O'Callaghan, Conor O'Shea, Padraic Guinan, Colm Cronin and Oisín O'Rourke saw them lead 0-13 to 1-9 with 58 minutes on the clock.
The visitors took the lead from the resultant free after Waterford senior star Colin Dunford was straight red-carded for a high tackle on an opponent. But Carlow goalie Enda Rowland rescued Carlow by levelling matters from a huge outfield free.
In the opening minute of extra-time a foul on Carlow's James Doyle in the large square saw James Owens award a penalty but 'keeper Rowland's effort was wide.
UCD availed of this let-off to go 0-16 to 1-11 at half time of extra time. Cronin's goal was the crowning glory for the visitors as they just held out in the face of strong Carlow pressure in the final minutes as the leeway was cut to a point.
The winners hit 15 wides over the course of the game to Carlow's eight.
UCD now go forward to the semi-finals at CIT next week.
O O'Rourke 0-8, 0-6f, 0-1 65; C Cronin 1-3, P Guinan, J Maher 0-2 each; C O'Shea (f), C Devitt 0-1 each.
E Rowland 0-5 (0-4f, 0-1 65), S Maher (0-4f) 0-5 each, J Fagan 1-0, C Dwyer, M Russell 0-2 each, C Dunford, K Kelly 0-1 each.
D Holohan; P Hannon, S Murphy, E Conroy; J Madden, C O'Callaghan, C O'Shea; H Lawlor, S Moran; J Maher, C Devitt, C Cronin; P Guinan, O O'Rourke, J O'Connor. Subs: C McGabhann for Moran (52); J Malone for Madden (64); J Phelan for Cronin (injured) (76). IT
E Rowland; K Hannafin, W Young, R Brown; D Healy, M Harney, D Palmer; M Russell, K Kelly; C Dwyer, J Doyle, S Maher; C Dunford, J Fagan, C Bolger. Subs: T Nolan for Maher (27); S Maher for Nolan (34); T Nolan for Bolger (50); M Kavanagah for Nolan (79).
Referee: J Owens (Wexford).
Video by Jerome Quinn Media for Higher Education GAA.