It proved third time lucky on the road for the Saints as they secured their first away league win of the season.
Two goals either side of half-time by Christy Fagan and Lee Lynch coupled with substitute Chris Forrester's injury-time strike saw the defending champions get their campaign back on track at a wet and blustery Carlisle Grounds.
However, a major downside to the result was the 82nd-minute departure of Ireland star Keith Fahey with a suspected hamstring problem.
Just as it seemed the sides would go in level at the break, the Dubliners snatched a 44th-minute lead.
Conan Byrne hung up a deep right wing cross and Fagan steered a looping header back across goal from eight yards.
Forrester was sprung from the bench for the start of the second period, and he needed just six minutes to play a crucial role.
His slide-rule pass released Lynch and he beat the offside trap to slot under the advancing Stephen McGuinness from 12 yards.
Bray rallied and scored off a training routine nine minutes from the end as Graham Kelly's corner picked out David Cassidy, who lashed through a crowded area from the edge the box.
But the Saints sealed the points two minutes into stoppage-time. Fagan held off Adam Mitchell to tee up Forrester who drilled low to the bottom corner from 18-yards.
Bray Wanderers – McGuinness; Cooney, Webster, Mitchell, Maloney; Scully (O'Neill 82), Zambra, Graham Kelly, Cassidy; Shane Byrne (Brown 86); Akinade.
St Patrick's Athletic – Clarke; O'Brien (McCormack 45), Browne, Hoare, Bermingham; Fahey (Quigley 82); Chambers, Lynch; Byrne, Kavanagh (Forrester h-t); Fagan.
REF – N Doyle (Dublin).