In a blockbuster match-up of two previously undefeated teams, the Demons showed their might in a tight encounter, winning 4.6 (30) to 3.1 (19) to move to 11-0 for the year.
The sides had been tied at half-time and United had taken a four-point lead heading into the final term, where it kicked the term’s only goal to hang on for the win.
Ellie Mifka, Alicia Laffy and Kate Adams led the way for United in a great display, while Abby Smyth, Hayley Doohan and Ashlee McMahon were in the action for the Bears.
The Bears remain second on the ladder and will look to exact revenge on the Demons come finals.
Elsewhere, Echuca came from behind at three-quarter time to knock off Seymour by two points in a thrilling game.
The Murray Bombers found the only goal of the last term, enough to win 5.4 (34) to 5.2 (32).
The result left them 7-1-3 for the season and fourth on the ladder, while Seymour is in sixth.
The Northern Angels showed their strength in a 21-point win against Tatura, in which they led from start to finish.
Andriana Oliver was in unstoppable form and kicked three goals for the Angels, with Charli Dorrity, Rani Guthrie and Katie Miller (two goals) also chipping in.
For Tatura, Georgia Steele, Sarah Lange-Richards and Tayla Albrey-Mills were in good form.
Moama looked in great form taking care of Mooroopna by 84 points.
In a one-sided showing, Jayda Richardson could not be silenced, slotting five goals.
Other monumental Magpies included Alexzandra Komiyama, Alivia Noonan and Lucy Williams, while Nerrissa Leitch, Leah Bates and Madelyn Andronaco did what they could for the Cats.