Wind-assisted Ardfinnan got off to a flying start with a pointed free by wing forward Michael Phelan within seconds of the throw-in.
But that would be their only score for all of 36 minutes' play and, with each passing moment the debutants grew in confidence. They had a towering midfielder in James Hyland who fielded some magnificent balls in the first half and he was ably assisted by attacking centre-back, Paul Frazer.
Up front, full-forward Benny Hickey, James McGrath on the wing and Pádraig Whelan in the corner were in inspired form, and when Hickey pointed a free in the fifth minute before McGrath, from a Michael Tarrant pass, extended their lead, an upset began to look likely.
Now Ardfinnan, despite wind advantage, struggled around the centre of the field. Scoring attempts from outfield went harmlessly wide while efforts to breach the Cahir rearguard were thwarted by a disciplined defence.
It may not have been pretty to watch, but the exchanges kept it interesting and there was always the chance of a goal that would turn the game upside down. Two such chances fell to Cahir within minutes of each other.
Robbie Halley, one of three last minute changes on the Cahir side, found Hickey, but his shot was blocked down by the Ardfinnan full-back, Alan John Lonergan after 16 minutes and it was Lonergan who again came to the rescue to thwart an almost identical attack a couple of minutes later.
Benny Hickey, later named Man of the Match, drove over a free from over 50 yards and then James McGrath and Padraig Whelan, from a difficult angle added two more to leave Cahir in front by a margin of 0-5 to 0-1 at half time.
If Ardfinnan had difficulty making use of the wind advantage in the first half, Cahir suffered the same affliction in the second. The losers were rewarded after seven minutes when Michael Phelan snapped up a Michael English pass to drive over a point their first in 36 minutes' play.
Phelan then added another from a free, and when substitute Paul Kennedy pointed another free after 53 minutes there was just one point between the sides.
Now Ardfinnan were pressing forward, but with Hickey now operating around the middle of the field and Thomas Maher and Michael English raising their game correspondingly, Cahir held out.
Scorers Cahir: B. Hickey 0-3 (frees), J. McGrath 0-2, P. Whelan and L. Kiely 0-1 each. Ardfinnan: M. Phelan 0-3 (0-2 frees), P. Kennedy 0-1 (free).
CAHIR: A. Burke; D. Lonergan, D. O'Gorman, P. Hyland; R. Costigan, P. Frazer, P. O'Flaherty; M. Tarrant, J. Hyland; R. Halley, G. Morrison, J. McGrath; P. Whelan, B. Hickey, G. Leahy. Subs: L. Kiely for J. Leahy (36 minis); G. O'Gorman for R. Halley (45 mins), D. Maguire for P. Whelan (61 mins).
ARDFINNAN: E. Ryan; T. Maher, A. J. Lonergan, N. Carrigan; M. English, G. Ryan, K. O'Brien; S. Maher, A. Keating; M. Phelan, T. Browne, P. Norton; A. O'Gorman, T. O'Leary, J. English. Subs: B. Lonergan for A. O'Gorman (24 mins); S. Sweeney for for A. J. Lonergan (33 mins); P. Kennedy for P. Norton (45 mins), P. Halley for T. O'Leary (54 mins).
Referee: Brian Tyrell (St. Mary's).