CATRIONA McConnell scored the crucial goal as champions Monaghan opened the defence of their Division 1 title by beating All-Ireland champions Cork 1-12 to 0-11 in Inniskeen.
Understrength Cork opened up an early four-point lead but McConnell's first-half goal put Monaghan on the road to victory.
Monaghan led by 1-5 to 0-5 at half-time and kept Cork at arm's length during the second half to record a valuable win, with Eileen McElroy, Sharon Courtney and Cora Courtney all in good form.
Meanwhile, Mayo began life under Peter Clarke with an impressive 2-12 to 2-6 win over Tyrone. Cora Staunton was the star as the Westerners marked their return to the top flight in style.
By half-time, Staunton had scored 2-3 as Mayo led by 2-4 to 1-6. Elsewhere, Laois collected maximum points from their trip to Donegal in a 1-16 to 1-9 victory.
Karen Guthrie scored 1-1 for Donegal early in the second half but Ciara Burke responded with a goal for Laois and that proved crucial.
In the Leinster derby, Lauren Ebbs and Amy Ring scored the goals for Dublin as the Jackies beat Meath by 2-6 to 0-10 at Fingallians.
In Division 2, Kildare needed a late goal to claim a draw against Galway in a cracking tie that finished 4-8 to 2-14. Kerry hammered Waterford and there were also wins for Fermanagh and Westmeath in Division 2.
Sligo, Leitrim and Tipperary got off to winning starts in Division 3 as Down and Armagh drew. And in Division 4, Limerick and Offaly enjoyed big wins away against Carlow and Derry respectively.