The Kangaroos led the whole way through but had to stave off a fightback from the Bulldogs who clawed back from a 43-point deficit in the final 20 minutes.

The Tamworth team ultimately booked another showdown with reigning four-time premiers the New England Nomads who have been unbeaten all year.

Kangaroos coach Tony Bishop seemingly had mixed thoughts about the preliminary final triumph, as scoring strongly favoured one end due to a strong breeze.

Bishop was disappointed with the final quarter as the result became a lot closer than it might have been. But he credited the Bulldogs for their resilience and their improvement as it was their first finals campaign for several years.

Bishop said the main aim for the Kangaroos was to reach the decider, after winning the 2011 title and being last year’s runners-up.

"It's why you play, (and) why you coach, to give your side a chance," Bishop said.

"We've reached our goal this year, and it's been awfully tough to achieve."

Bishop conceded that the player commitment at training had not been up to scratch, and that "it's been a real battle to get to where we are".

"But they (the Kangaroos) showed some heart today against a team that showed plenty of heart."

On a field that held up well despite being sloppy in the cricket pitch area, Tamworth opened the scoring with a behind before Boe Gilmour landed the opening goal.

Dan Overeem's first goal took Tamworth to a 14-point lead before player-coach Greg Piggott opened Gunnedah’s account with a goal, and the Kangaroos established a 20-point quarter-time lead.

Piggott kicked the first goal of the second quarter, but the Kangaroos moved 27 points clear before Piggott's team recovered to trail just 6-6-42 to 5-5-35 at the main break.

Matthew Hodge kicked a great goal from the sideline early in the third quarter, which the Kangaroos dominated with four goals and five behinds while keeping their opponents scoreless.

Overeem kicked the first goal in the final quarter, but the Bulldogs refused to consider they were beaten.

Mitchell Swain and Piggott landed a major each in quick succession, before Ben Maher bagged two goals in four minutes.

Piggott lowered the margin to 10 points with a little under five minutes remaining to keep alive the possibility of a spectacular come-from-behind victory.

The pendulum changed as Gilmour took a mark and kicked a goal with two minutes left to stretch the margin to a virtually insurmountable 16 points.