In the SSE Airtricity Premier Division, champions Shamrock Rovers suffered a shock defeat to Waterford, losing 3-1 at Tallaght Stadium.
Shelbourne scored late on to earn a 1-1 draw with Derry City at the Ryan McBride Brandywell.
Paul McMullan had put the Candystripes in front, but a 19th minute Sean Boyd strike means Damien Duff's side remain three points clear at the top of the table.
Elsewhere Drogheda United defeated Dundalk 2-1.
Sligo Rovers defeated Saint Pat's 1-0.
And Bohemians lost 1-0 to Galway United.
