Shamrock Rovers claimed the bragging rights over rivals Bohemians with a 3-1 win at Tallaght Stadium.
Two goals in the space of four minutes from Johnny Kenny and Darragh Burns put the reigning champions in control, with Aaron Greene securing the win in the 74th minute.
Bohemians scored a consolation through Declan McDaid in the 94th minute.
In tonight's other games, Shelbourne remain top of the table with a 2-0 win over Dundalk.
Liam Burt scored the first goal of the game in the 51st minute, with an own goal from Hayden Miller putting the game beyond reach for Dundalk.
Robbie Benson pulled a goal back in added time for Dundalk, as their struggles continue as they remain without a victory this season.
In second place is Sligo Rovers after their 1-0 win over Waterford.
Ellis Chapman scored the winner in the 53rd minute, with Sligo Rovers reduced to 10 men with Simon Power.
Stephen Walsh scored an 85th goal for Galway United to give them victory away to Derry City, while it finished 0-0 between Drogheda United and St Patrick's Athletic.
