For the second week in a row City were reduced to an Aussie-dominated eleven following the early injury withdrawal of Ritchie De Laet. Their sole element of foreign experience, Bart Schenkeveld, was key to offsetting United's early dominance.
Melbourne City then drew first blood through a Jordan Elsey own-goal, Ramy Najjarine finding Riley McGree in space by the touchline, the midfielder sending a venemous cutback into the net off the United defender.
Warren Joyce's side, especially the young up-and-comers who make up their depth and breadth, are capable of playing excellent football.
It's what you'd expect from a former Manchester United reserve coach (there's no shortage of them involved in Oz football at the moment) but it creates its own frailties, most notably a lack of cohesive structure defensively.
As a result, the match often became a series of exciting counters and acres of space on the wing. But City were ruthless in possession, largely down to their exciting youngsters - Socceroos fans will pay close attention to Najjarine's development in particular.
Both the 18-year-old and Elsey played key roles in City's second, the latter ousted by the youngster, whose cut back found Luke Brattan, a strong strike all that was needed to beat a disappointed Paul Izzo.
After that it was all slick City passing, Craig Goodwin howlers and last-ditch defending, with Bart Schenkeveld a standout Man of the Match. 
"I think with young kids on the right side they do really well," Schenkeveld began, "But technically they need to learn, on the left side with a few crosses as well, they made it hard for us.
"We press really well and it felt difficult to press through us, but in the last 20 minutes I could play my balls. The second half was box to box, it was open, it wasn't beautiful, but we needed the win.
"The young lads need to learn that they can beat everybody. For me, Eugene Galekovic was man of the match, it's great to have him behind me."
Conversely against his former club, United centreback Michael Jakobsen was a man of few words, notably, that they weren't "happy".
"First half we were in the game, creating the chances, but the first opportunity they get we created an own goal," Jakobsen said.
"The last 20 minutes we're not happy with. When they score outside the area, it was their only chance, we're not happy today.
"I'm not happy with my passing today, it should be better. They let us be on the ball so we need to have a lot of passes, but it's something we're working on everyday."
The win moves an inconsistent City side to fourth, once again alleviating pressure on Joyce while leapfrogging fifth-placed United. The real test of both sides' development comes next week; City have a Melbourne derby while Adelaide face low-hanging Newcastle.