In other big round 12 selection news, Sydney lost captain Callum Mills to a calf niggle and decided to rest ruckman Brodie Grundy, Jacob Weitering is back for Carlton, and Bulldogs ruckman Tim English is over his concussion.
Zorko has missed the past fortnight with a quad niggle, and fresh scans have revealed more damage than the initial injury, ruling him out for up to six weeks.
"He felt sore again at training last week, and scans have revealed he's got more damage there than he's got previously," Lions coach Chris Fagan said.
"It's just one of those things in the rehab process. All rehab processes don't go perfectly unfortunately."
Zorko's absence has coincided with a big drop in form by Brisbane, who have lost to Geelong (41 points) and GWS (78 points) over the past fortnight.
The Lions will be aiming to bounce back in Saturday's night's clash with Fremantle, who have regained skipper Alex Pearce (knee) but will again be missing Hayden Young (concussion) and Caleb Serong (calf).
Brisbane have been boosted by the return of Jarrod Berry (calf) and Noah Answerth (concussion).
Sydney have made four changes from last week's 27-point loss to Geelong after Mills joined Tom Papley (calf, six weeks), Malcolm Rosas Jr (ankle, 1-2 weeks) and Grundy (rested) on the sidelines.
Harry Kyle, Harry Cunningham, Peter Ladhams and Hayden McLean were handed recalls for Saturday's meeting with Richmond at the SCG.
Tigers spearhead Tom Lynch (throat) and Jonty Faull (concussion) joined Richmond's lengthy injury list, but Richmond at least get Dion Prestia and Sam Banks back from injury.
All-Australian defender Taylor has been named in the Giants' extended squad alongside the likes of Lachie Whitfield and Leek Aleer for Sunday's clash with Melbourne in Alice Springs, but Jack Buckley (hamstring) and Jake Riccardi (ankle) have already been ruled out.
The Demons lost Jake Lever and Changkuoth Jiath to injury, but could welcome back Tom McDonald and Brody Mihocek.
Essendon caretaker Dean Solomon has made five forced changes for Sunday's meeting with West Coast.
Andrew McGrath, Mason Redman, Sam Durham, Jye Caldwell and Matt Guelfi are all injured, with Nik Cox, Elijah Tsatas and Will Setterfield among the potential inclusions.
Weitering and Blake Acres are back for Carlton on Friday night, with Geelong boosted by Tanner Bruhn's return at the expense of Jack Martin (rested).
Collingwood, who have lost Darcy Moore, Jamie Elliott and William Hayes to injury, get Tim Membrey back and have also handed a recall to Harvey Harrison for his first AFL match since injuring his ACL in 2024.
