Drogheda United 0 Shelbourne 3
Shels went second as Drogheda slumped to a third defeat on the spin.
Shels took the lead on 34 minutes when Mark Roberts powered home a header from a Wes Houlihan free kick after Stuart Byrne had been fouled.
Shels sealed the points on 56 minutes when Stephen Geoghegan headed against the bar from David Crawley's cross and Barry Prenderville fired home the rebound.
Geoghegan then missed a penalty before Crawley added the third from the spot on 85 minutes.
Declan O'Brien also missed a late penalty for Drogheda.