Stephanie Roche marked her return to the Women's National League after six years away with a goal as champions Peamount United cruised to a 5-0 opening-day victory over Treaty United.
James O'Callaghan's team didn't waste much time in getting off the mark when Alannah McEvoy slid a pass through for captain Aine O'Gorman and she drove her shot past goalkeeper Michaela Mitchell.
O'Gorman repeated the same trick inside the opening 25 minutes when she met a Karen Duggan pass and showed why she remains one of the league's most clinical finishers.
Mitchell pulled off a number of excellent saves as Treaty, making their league debut, tried to fight back.
But a deflected goal plus strikes from McEvoy and the returning Roche sealed the win.
Fellow league debutants Bohemians were also given a stark introduction as they were beaten 4-1 by Wexford Youths.
Lauren Kelly, a brace from Ellen Molloy and Vanessa Ogbonna accounted for the goals for Wexford, but Chloe Darby's consolation should give Bohemians heart for next weekend's clash with Galway, who opened their season with a 1-1 draw against DLR Waves.
Shelbourne, meanwhile, got under way with an impressive 3-1 victory over Cork City, with captain Pearl Slattery heading home the opening goal. Ciara Grant added a second as the Dubliners dominated before Rebecca Cooke registered their third goal.
Saoirse Noonan converted a consolation penalty for Cork.