The visitors got out to a one-goal advantage at the first change at Princess Park, a lead they would slowly build on throughout the contest.
The Swans attempted to rebound in the second quarter and could have surged to a comfortable lead but for some wayward shooting, kicking four behinds.
United managed a third goal after the main break and held on from there to seal its third win of the campaign.
Olivia McGie was best-on ground for the visitors after a strong performance, while Elissa Down, Lila Guthrie, Matilda Henderson, Ella Moroney and Miley Guppy stood out.
An even contribution from the Swans was reflected on the scoreboard too, with Emily Zampaglione, Zahra Kelly, Charli Guppy and Henderson finding the big sticks.
In the other youth encounter, Moama cruised to a solid 9.17 (71) to 1.3 (10) win over Echuca United.
Miranda Ham, Katie Shanon, Payton Hearn and Shaleah Cooper kept the scoreboard ticking over for the Magpies with two apiece.
In senior action, Echuca recorded a dominant victory over Benalla at Victoria Park on Sunday.
Nursing no less than seven injured players, Echuca still had enough in the tank to deliver the Saints a hefty 15.4 (94) to 1.2 (8) defeat.
Paige Baksh was clinical in front of goal, kicking six, while Eimer Draper, Ellie Wright, Jacqueline James, Remy Day and Jordan Irvine provided class support across their lines.
The remaining senior match between Nathalia and Shepparton United was abandoned.
