Up and down permutations
Cork's place in the final is secured. Even if they lose to Mayo in their last game and Dublin beat Tyrone in Omagh to match them on 10 points, their head-to-head with Dublin, the criteria being used when the two teams are level, determines that they will join Mayo.
If Mayo lose to Cork and Dublin beat Tyrone to join Mayo on 10 points Dublin's win in Castlebar earlier in the month will ensure a repeat of the 1999 final.
At the other end, the permutations are many and complicated involving four teams, so we'll take the two most likely scenarios -- Kerry to beat Monaghan in Killarney and Tyrone to beat Dublin in Omagh. In that case Monaghan and Derry will go down.
Derry's score difference is so poor that even if they did force a three-way tie on four points they would be the first team down.
A Monaghan win in Kerry would sink the reigning league champions if Dublin beat Tyrone and Galway triumph over Derry. But if Derry got a result against Galway it would force a three-way tie between Kerry, Derry and Tyrone.
Tyrone will go if Derry lose to Galway, they lose themselves to Dublin and Kerry beat Monaghan, because that will leave them tied with Monaghan, who won their previous head-to-head in Inniskeen.
As straightforward as it gets. Down are promoted and awaiting the winners of Armagh and Donegal, who meet in Ballybofey, in the last round.
At the other end Tipperary and Westmeath have already been relegated.
Antrim are promoted for the second successive season and await either Sligo or Wexford. Sligo's prospects are better as they meet already relegated Roscommon.
Wexford host Antrim. Wins for both Wexford and Sligo would suit Wexford, who would progress on the head-to-head result.
In the unlikely scenario of both Sligo and Wexford losing, Cavan's score difference could be telling if they beat Fermanagh. Roscommon and Fermanagh's fate is sealed as they drop to Division 4.
With two rounds left Clare have a strong hand but they face their nearest challengers over the next two weekends in Limerick and Waterford.
If Clare beat Limerick on Saturday they will ensure that Waterford and themselves are promoted.
Waterford and Limerick both have Kilkenny in their last two rounds which makes the Clare/Waterford game of paramount importance if Clare don't beat Limerick.