Trevor 'Billy Boy' Molloy scored a cracker of a goal from the tightest of angles to ensure all three points for The Supersaints at Tolka Park.
The strike on the stroke of half time, was a reminder to watching Ireland Under 21 Manager Ian Evans of just how Molloy can turn a game as the striker's rich vein of form continues.
Yet again another huge travelling army of Supersaints witnessed another pulsating encounter at the Drumcondra venue.
Pats played with three at the back again but without the services of Colin Hawkins and Thomas Morgan - both on International duty.
The system seemed to be working as they soaked up early Shels pressure, Trevor Croly making a goal-line clearance after 14 minutes from a Tony McCarthy header after a corner from Pat Fenlon.
The midfield trio of Osam, Gormley and Russell came more into the game as the half progressed and it was Martin Russell who had the best of the visitors' chances with two long range efforts - one that hit the upright with Gough in the Shels goal well beaten.
Central Defender Pat Scully was sent off after 24 minutes for a second bookable offence and Pats made the extra man count when Molloy pounced after a Martin Russell free kick found him wide on the right.
Second half substitute Martin Reilly had the best scoring opportunities for the Supersaints after half time with a dazzling run from the left thrilling the away fans on the Riverside end. Reilly cut inside only to see his shot drift agonisingly left and wide.
Shels threw everything at the Pats defence but it was to no avail and Pats stay three points behind leaders Cork City with a sizeable gap now opening up between these two and the rest at the top of the FAI National League table.
Former Inchicore hero Ricky O'Flaherty, recently signed by Dermot Keely for Shelbourne came on after 55 minutes and received a terrific welcome form the St Pats fans.
Luckily for the Supersaints, Ricky failed to make an impression in the difficult windy conditions and a less than smooth playing surface.