West Coast players will become temporary Adelaide and Sydney fans this weekend - but first they need to get the job done against North Melbourne at Metricon Stadium on Thursday night.
The fifth-placed Eagles will jump into third spot with a win over the struggling Kangaroos.
But staying in the top four will prove to be more difficult, with West Coast needing either the Crows to beat Richmond in Adelaide on Saturday, or Sydney to beat Geelong at Metricon Stadium on Sunday.
Adelaide (3-13) sit last on the ladder, while Sydney (5-11) haven't fared much better this season.
If Richmond and Geelong can avoid a boilover West Coast will finish fifth, thrusting them into an elimination final instead of having a prized double chance.
Eagles coach Adam Simpson said it was an exciting way to finish the regular season.
"We need to win, and then we need another team to lose," he said.
"This last round presents different scenarios, and I'm sure everyone is watching this weekend with excitement because there's that many different ways the season can finish up."
North Melbourne have lost 13 of their past 14 games to crash to 17th.
If they lose to the Eagles and Adelaide upsets Richmond, the Kangaroos will collect their first wooden spoon since 1972.
Coach Rhyce Shaw conceded North Melbourne weren't up to standard in last week's 64-point loss to Fremantle, and he's hoping they rebound strongly against the Eagles.
Simpson is by no means treating the game as an easy one.
"Being the last round of the year, from North's point of view it's an opportunity to put their best foot forward," he said.
"They haven't been great the last few weeks, I think Shawy is the first to admit that.
"But we're going to plan for them at their best. At their best they bring a lot of pressure and they're very contested base."
West Coast have lost star defender Jeremy McGovern to a hamstring injury but welcome back midfielder Dom Sheed and forward Brendon Ah Chee.
The Kangaroos recalled defensive duo Tom Murphy and Sam Durdin in place of Aiden Bonar (shoulder) and forward Mason Wood (dropped).