The Mariners led at quarter time but from there the Maroons got on top and outworked Tasmania to record an 8.18 (66) to 4.3 (27) victory.

State under-18 coach Adam Sanders was disappointed with his team's performance which was well below that of their first game of the championships against New South Wales-ACT.

"We were very poor today and it was a stark contrast to last week's performance," he said.

"It was very disappointing and the boys are disappointed in themselves and it is not the happiest place at the moment.

"Queensland's pressure and tackling was much better - they virtually did to us what we did to NSW when we outworked and out-tackled them.

"They targeted some of our guys and really pinned them down and the were a bit too tall for us and too strong and we struggled to contain their 200-centimetre forward who kicked four or five goals.

"They probably should have won by more if they had kicked straight so back to the drawing board."

Good players were hard to find for the Mariners but Sanders said North Launceston's Logan Reynolds tried hard in defence as did Launceston's Jack Donnellan in the first half before injuring his shoulder and taking no further part in the game.

"Harry Pearce from Glenorchy was OK as a half-forward and Jordan Hayden was OK through the midfield and won enough of the ball but other than that they were hard to find."

Tasmania faces Northern Territory in their final game of the carnival on Wednesday.

"We've had a very honest review and you have to move on quickly and can't do too much training between now and Wednesday," Sanders said.

"It was just a mindset thing and I think they went in a bit overconfident and that's what happens - you get your pants pulled down when you do so hopefully it is a good learning curve for them."