MK Dons are staring down the barrel after a 2-0 defeat at Bradford on Tuesday left them languishing six points from safety with two games to play in League One.
Keith Millen's team also have a significantly worse goal difference than the sides immediately above the drop zone and require a 13-goal swing to beat the drop.
AFC Wimbledon, who have 50 points with three games to play, are themselves not clear of danger, but crucially can't be caught by their rivals from Buckinghamshire.
AFC Wimbledon were formed 16 years ago when Wimbledon FC, nicknamed The Dons, controversially relocated to Milton Keynes and subsequently became MK Dons.
Phoenix club AFC started life in the Combined Counties League - the ninth tier of English football - in 2002 and have since won six promotions, reaching League One via the play-offs in 2016.
Meanwhile, MK Dons are set to drop into League Two for the second time since the move north and, should AFC Wimbledon survive, will be playing a tier beneath Neal Ardley's men for the first time.