Crusaders ended a three-game losing streak with a hard-earned triumph at Coleraine, their third league success over the Bannsiders this season.
Blaney headed the visitors in front on the half hour before second half substitute Harry Jewitt-White sealed the win with a breakaway goal deep into added time.
The home side missed a litany of chances in the early stages before Crusaders broke the deadlock.
Rhyss Campbell blazed wide from a good position, Connor Murray was denied by a good save from Jonathan Tuffey while Matthew Shevlin failed to convert when through one on one with the Crusaders’ keeper.
They were made to pay for their profligacy when the visitors scored with their only chance of the half.
Ross Clarke delivered a free-kick to the back post where Blaney outjumped the home defence to nod past replacement keeper Max Little, on for the injured Rory Brown, hurt in a challenge with Harry Franklin in the early stages.
The game followed a similar pattern after the restart as Murray’s curling effort crashed off the crossbar and Johnny Tuffey dived low to deny Dean Jarvis.
Second half sub Corey Smith was denied by a fingertip save by the impressive Tuffey before moments later crashing a right foot shot against the post with the keeper beaten.
The points were secured deep into added time when Josh O’Connor broke free down the left wing before squaring for unmarked fellow second half replacement Jewitt-White.