Clarence's development league side were too strong in Launceston's pursuit for back-to-back titles, defeating the Blues 12.2 (74) to 8.12 (60).
Roo Bryce Alomes was massive through the game's crucial stages, booting five majors in the win as Jacques Barwick joined the party later on but it was teammate Luke Swinton who took out the best-on-ground medal.
The Blues controlled a majority of the play in the opening minutes but were unable to convert on the scoreboard, while the Roos made them pay.
A brilliant run by Barwick down the Western wing saw him find Jacob Young despite being outnumbered for the first major of the day.
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Bryce Alomes added another to the board to a roar from the visiting Clarence crowd as the younger Blues tried to chase their tail.
Their defence stood tall despite momentous pressure from the visitors, running forward against the momentum through Jake Rice, finding Jett Maloney for their first of the day.
Making the most of their opportunities, Clarence took a two-point lead into the first break and looked to add to that with a stunning Wade Wall major in the opening minutes but a touch off the boot was called.
It wouldn't be long until they however, as Jack Callinan found Alomes in the goal-square with a brilliant centring snap.
Alomes converted for his second but Grant Holt pegged back the lead, making no mistake from 35 metres out.
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A down-field free-kick saw tempers flare and eventually Maloney was able to convert the free, bringing the Blues back into the lead for the first time since early days.
James Dowling extended it but Alomes would be the man again, adding the Roos' next two to make it four in a row for him as the Blues struggled to find the big sticks.
The pair went into the main break all tied up but Sam Foley's roving put the Blues back in front in the first two minutes as scoring began to slow.
However, after an electric five-bounce run from Blue Colby McKercher, the Roos struck back, with Alomes booting his fifth, Wall taking a hanger and Howlett putting one through.
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Ronan Filgate swung one back but the Roos went again through Barwick, putting the margin at a game-high 12 points once again.
Having scored four of the last five, the visitors had the run until McKercher stood up after looking dangerous for the term, giving the Blues a late one heading into the last.
Having lifted in the third term, Brayden Pitcher missed the Blues' first chance of the last, putting them within four points.
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That miss would prove to be the only score in the first 12 minutes of the term until Arie Schoenmaker's outside-50 shot was punched across the line, edging the Blues closer.
A promising Blues attack was foiled by a cracking contested mark from Oliver Preshaw, setting the Kangaroos up for their counterattack, getting it down the other end to Barwick.
The speedster slotted it through before doing so again a minute later as his two goals and Liam Howard's put the icing on the cake.