CHRIS Fagan believes the heartache of last year's Grand Final loss helped drive Brisbane to one of the great September comeback victories on Saturday night.

Trailing by 44 points during the second half, Fagan reminded his team that Greater Western Sydney had coughed up a hefty lead against Sydney just seven days earlier.

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He told them to keep taking the game on, "dancing on thin ice", as they have for the second half of the season.

The result? A withering final quarter capped by two brilliant Joe Daniher goals that piloted the Lions into a preliminary final against Geelong next Saturday afternoon.

"I'm trying to keep control," an emotional Fagan said in his post-match press conference.

"You don't often have days like that in footy and that'll be one I'll never forget.

"It was just one of the great comeback wins.

"I'm very proud of the group. We stuck to our guns and when everything looked lost, we hung in there … it sort of summed up our season."

This is the sixth straight finals campaign for the Lions since Fagan took the coaching job at the end of 2016, with next week their fourth preliminary final appearance in that stretch.

When asked whether he thought Brisbane's players drew on the Grand Final loss to Collingwood last season as a source of inspiration, Fagan agreed.

"I know they're desperate to get back there and have another crack," he said.

"I've got no doubt that drives them.

"I look at Dayne Zorko and it drives him. He's 35, he doesn’t know how many years he's got left in the game.

"He desperately wants to win one. I think that drove the group.

"Joey Daniher is the same.

"The guys in our team that are a little older, they lifted in that last quarter, I've got no doubt about that."

Fagan said despite the big deficit he always felt Brisbane was a chance after gifting the Giants a handful of goals during the pivotal second quarter.

He said at half and three-quarter time he reiterated to his team the importance of playing bold and continuing to attack.

Brisbane slammed on five consecutive goals during the third term to reduce the margin to 13 points, but the hosts steadied with three goals either side of the final change to again seemingly put the result out of reach.

But the Lions kept coming, with the coach reminding his team of Sydney's come-from-behind win a week ago.

"I did say that that happened last week.

"Sometimes in sport history repeats and it can be something in the back of your mind if it gets close enough.

"I don't know whether it did that or not, but we just had to give ourselves a chance to see if that would happen.

"We talked about it. We had to find things to stay positive, so it was worth talking about.

"When you're in the situation we were in, I'd rather go down by a large margin having a crack than just falling off the perch."

It will be the third time Brisbane has faced Geelong in a preliminary final under Fagan, following losses in 2020 and 2022.

The latter came after a semi-final win over Melbourne at the MCG, and with that in mind the coach said his team would have to put the Giants win behind it quickly.

"it was such an amazing night for our footy club, but to let it go on for too long would be a mistake.

"Geelong are sitting back waiting for us. We were in this position before a couple of years ago … we need to do a better job than we did then.

"That'll be fresh in our players' minds, they won't forget that.'