Harlequins are finding it difficult to haul themselves away from the relegation zone - even on their own patch - as Terenure assembled a 26-8 lead in the second half before allowing their hosts to gain a temporary foothold in the closing stages.
Richard Governey's accuracy with the boot laid the foundation for Terenure's victory in the first half after he had hoisted over three penalties which gave his side a 9-8 interval lead, David Irwin having crossed for a Harlequins try following a Paul Handcock penalty.
However, it was in the third quarter that Terenure took up the reins, particularly after Belfast Harlequins hooker Richie Weir had been sinbinned. Karl Hammond pounced for a try for Terenure which Governey converted; and the Dublin side swiftly turned the screw when substitute hooker Cormac Egan and industrious prop Steve Barretto both crossed the home line.
Harlequins opted for adventure as the game ebbed to a close with Andy Park and Sheldon Coulter snatching tries to keep their faint hopes of a complete recovery alive.
But Terenure had the final say when centre Michael Smyth created the opening for Derek Hegarty to put the seal on an accomplished performance by the visitors by pouncing for a late try which Governey converted.
BELFAST HARLEQUINS: N Malone; A Park, S Coulter, S Dick, R Morrow; P Hancock, D Jack; S Best, R Weir, D Scott, K Rabie, D Irwin, G O'Loan, C McCarey, N Best. Sin-binned: Richard Weir.
TERENURE: G Dempsey; D Coleman, M O'Kelly, M Smyth, S Cullen; R Governey, D Hegarty; S Barretto, J Blaney, J Campbell, C Long, D Quinn, A Ryan, K Hammond, P O'Malley. C Egan (try).
Referee: D Keane (Leinster).
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