The Lions will play Geelong in an MCG qualifying final after defying poor goal-kicking to beat Hawthorn on Sunday night and lock in third spot.
The 10-point win came without midfielders Lachie Neale (quad) and Jarrod Berry (shoulder) and forward Eric Hipwood (calf).
Neale and Berry are all-but certain to play against the Cats while Hipwood is doubtful.
Brisbane also dealt with Jack Payne, Noah Answerth, Keidean Coleman and Lincoln McCarthy's long-term injuries to buck the trend of recent champions and mount a compelling title defence.
Hugh McCluggage, seemingly destined for a maiden All Australian blazer this year, has elevated his game to offset those losses.
Fagan hopes McCluggage earns that nod but the coach issued a not-so-subtle reminder of the younger talent at the club's disposal too.
"We'll get a few back, but the boys that played stood up," he said.
"We had nine players 22 or under; it's not an old team and if you look at it, Hawthorn were about a year older than us on average age.
"A lot of those young boys are really good players, not frightened of anything and we'll back them in during the finals series."
Darcy Wilmot, 21, was electric surging out of defence on Sunday.
"When he gets the ball, things happen," Fagan said.
"He takes ground, uses the ball well, he takes the game on.
"Nothing worries him ... he's the ultimate goldfish. I love the way he plays his footy."
The Lions lost just once during the home-and-away season outside of Queensland, a string of late behinds costly in a 10.8 (68) to 8.15 (63) defeat to the Crows at Adelaide Oval.
Fagan, in his ninth season in charge at Brisbane, rates it their best campaign but knows how small the finals margins are.
"It doesn't take too much to get it wrong, and it doesn't take too much to get it right," he said.
"We're in there with everybody else, but we're going to have to play our best."