Four goals were scored in the opening half as the sides were level at 3-1 to 1-7 at the break.
Harps had four points on the board before Kilmaley opened their account with sixteen minutes on the watch.
Kilmaley’s Maria Hehir and Harps star Mahony traded goals before the Clare kingpins shocked their opponents with a quickfire brace from Claire McMahon just before half-time.
With two minutes remaining in the first half, McMahon’s free deceived the Harps defenders and ended up in the net before the same player struck again from play to hand Kilmaley a one-point lead.
Player of the match Louise Mahony converted a 45 to tie the scores at half-time and as Kilmaley shot five second half wides, Harps made better use of the chances that came their way to seal the three-in-a-row.
Scorers for Harps: =C Mahony 1-3 (0-3f), Aisling Phelan 0-3, Joanne Prior 0-1, Louise Mahony 0-3 (1f, 1 45), Angela Hannon 0-1.
Scores for Kilmaley: Claire McMahon 2-2 (1-2f), Maria Hehir 1-0.