Monaghan retained division one status for a tenth successive year after beating Mayo 2-14 to 0-14 at Castlebar.
The sides were level 11 minutes from time but Monaghan emerged victorious after a strong finish.
Monaghan started impressively and Ryan O’Toole’s goal on 13 minutes helped Monaghan to a five-point buffer on 25 minutes.
Mayo eventually settled and scores from Paul Towey (two), Jordan Flynn, and Bob Tuohy made it a one-point game seven minutes later.
Jack McCarron and Matthew Ruane subsequently traded a point each as the visitors held on to lead 1-6 to 0-8 at the break.
McCarron restored Monaghan’s three-point cushion five minutes into the second half. 14 minutes later Jordan Flynn restored parity.
The Farney men subsequently regained the upper hand; Conor McManus gave them a three-point cushion one minute from time.
Ryan O’Donoghue reduced the margin to a solitary point 60 seconds later. Monaghan responded by heading 1-1 without reply in injury time.
Stephen O’Hanlon slotted over a point before a penalty goal from Conor McManus sealed an important victory right at the death.
Top-flight survival was guaranteed after Tyrone defeated Armagh 0-18 to 0-16 at Omagh. Armagh and Donegal drop down to the second tier.