SATURDAY night's semi-final result against the Western Bulldogs will not define Brisbane, win or lose, says coach Chris Fagan.

Since their ascent into the top four in 2019, the Lions have won once in five finals appearances, bowing out at the semi-final and preliminary final stages the past two years.

Fagan hasn't given any thought to the pressure of a positive result, saying he maintained a broader view of Brisbane's progress.

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"We're a young developing team," Fagan said on Friday.

"Two years ago we couldn't get off the bottom of the ladder.

"Part of the process of becoming a great side is getting into finals, playing and doing your best to win them and letting those experiences build.

"We played a great team last week in Melbourne who have been on top of the ladder pretty much all of the year and they played exceptionally well.

"Win or lose, that result doesn't define us or have you guys (media) described us as a team that can't play in finals."

Fagan highlighted the path of Richmond before its three-premierships-in-four-years run, where it lost successive elimination finals in 2013, 2014 and 2015 before missing the top eight altogether the following year.

"It's all about the learning process, the hardening process," he said.

"Either way, whichever way the game goes tomorrow night we'll be a better club for it.

"Hopefully it's in the positive and we keep going into the season. 

"I have a bigger picture, philosophical view on finals than just the immediate result."

Brisbane has made two changes from the team beaten by the Demons, recalling young pair Jack Payne and Deven Robertson at the expense of concussed forward Dan McStay and utility Jaxon Prior.

Fagan was coy about his team's forward set-up in McStay's absence, saying Marcus Adams and Harris Andrews were both chances of spending time inside the forward 50.

His main area of concern from last week was the defensive side of the game.

"We did not defend the ground well on Saturday night and it was too easy for Melbourne to go from one end of the ground to the other," he said.

"It was a dirty side to our game we weren't happy with.

"Hopefully we'll get an improvement in that tomorrow night.

"I generally find if our defensive game is on, everything else falls into shape."