The Greystones school looked for space straight away, while Wesley preferred a more pragmatic route forward.
The first real crack came when Wesley won a scrum against the head for number eight Peter Costello to take the ball on.
The recycle came for full-back Jamie Metchette to stretch the defence going left.
A penalty was conceded by Temple and they were punished when captain Jamie Kavanagh went quickly and Metchette popped up on the left to skate in for 5-0 in the 10th minute.
Temple Carrig looked to number eight Patrick Kieran, and centres Cian Hingerty and Jack Ryan to take it to their opponents.
Slowly, Wesley owned more of the territory as their driving game kept them in the right areas.
It left Temple looking to strike from distance, a risky business, from out-half Sean Mason’s distribution.
Wesley’s centre Luke Fitzpatrick and big lock Tadgh O’Neill made inroads before the breakdown let them down.
Mason was always probing for an opening and it was his eye for space that forced a lineout on halfway.
From there, Ryan thundered on and his offload found Kieran with the legs to get away from the defence for the tying try.
Mason converted for 7-5 on the half-time whistle.
Wesley had to be vigilant when captain Kieran burst clear to put wing Max Patton in a promising position until closed down by Metchette.
A high tackle allowed full-back Thade Shanahan to find the corner and Wesley’s Daniel Fives was binned for the indiscretion.
A phenomenal carry by centre Ryan took Temple right up to the line.
It was enough for a scrum and Conor Fulham broke right to feed Max Patton for their second try in the 44th minute.
They had something to really protect and replacement James McGoldrick had to be stopped in his tracks to keep it that way.
Wesley looked to lift the tempo, scrum-half Jack Atkinson tapping a penalty.
The pressure caused flanker Zach Evans to be binned under severe pressure.
Number eight Peter Costello carried with intent and lock Tadgh O’Neill drove over to narrow the difference to 12-10 in the 57th minute.
They came again, centre Fitzpatrick raiding down the right without being able to get away.
But that was it. Temple had survived. History had been made.
Temple Carrig 12 Wesley College 10
At Donnybrook – TEMPLE CARRIG 12 (P Kieran, M Patton try each; T Shanahan con); WESLEY COLLEGE 10 (J Metchette, T O’Neill try each)
Temple Carrig: Thade Shanahan; Josh Sproul, Cian Hingerty, Jack Ryan, Max Patton; Sean Mason, Conor Fulham; Jordon O’Connor, David Prendergast, Cormac Coffee, Joe Barford, Killian Burke, James Clark, Zach Evans, Patrick Kieran (capt).
Replacement: Josh Hayden for Coffee 44 mins.
Wesley: Jamie Metchette; Mattias Hjelseth, Luke Fitzpatrick, Timothy Elliott, Nathan Columb; Max Collins, Jack Atkinson; Christopher Gilmer, Jamie Kavanagh (capt), Jack Fish, Tadgh O’Neill, Tadgh Maguire, Daniel Fives, Thomas Dunne, Peter Costello.
Replacements: Jamie McGoldrick for Columb 7 mins; Adam Evans for McGoldrick 51 mins.
Referee: Jonathan Geoghegan, Leinster Branch