Behind a powerhouse performance from Shamera Sterling, the Thunderbirds roared home in the fourth quarter at USC Stadium to break through for their maiden win over the Vixens in Suncorp Super Netball.
Melbourne came into Sunday's clash unbeaten after three rounds having conceded the fewest goals in the competition but it was the defensive effort from the upstart Thunderbirds that proved the difference.
Jamaican import Sterling thwarted numerous Vixens attacking plays with nine deflections, three defensive rebounds and two intercepts.
"I haven't been playing my best netball but today I was determined enough to come out here and say 'Hey Shamera, you need to put your best game on'," Sterling said after her match-winning effort.
Coming off a 15-goal defeat to the NSW Swifts, the Thunderbirds applied relentless pressure to their highly-fancied opponents from the outset as they held the Vixens to their lowest scoring quarter for the season in the first period.
Melbourne still held an 11-10 lead heading into the second quarter and extended their advantage to five but Adelaide clawed their way back in the rebel Power5 period, the Vixens needing a late Tegan Philip goal to grab a 23-22 advantage at halftime.
The Thunderbirds refused to go away in the third term with rookie goal attack Georgie Horjus sinking a Suncorp Super Shot to put her side up by three goals approaching the end of the quarter.
But the experience of shooter Caitlin Thwaites came to the fore as she responded with two super shots of her own to put the Vixens up 37-35 heading into the fourth quarter.
With their unbeaten record on the line, Melbourne tried valiantly to find a way through Adelaide's rock-solid defence but the underdogs would not be denied, 18-year-old Horjus keeping her cool with some clutch shooting from two-point range to seal a memorable victory.
Adelaide will be chasing their third win of the season on Wednesday night against Collingwood Magpies while the Vixens have 48 hours to prepare for Tuesday night's clash with West Coast Fever.
