Bakhtiari had already been ruled out of Thursday night's game against the Lions but now will miss at least three more games after that. His earliest possible return is Nov. 5 against the Rams.
After playing in the season opener, Bakhtiari missed the next two games before Thursday's move.
This all stems from the Dec. 31, 2020, knee injury he suffered in practice. He had three surgeries on that knee since the injury and has missed 24 of a possible 47 regular-season games since the start of the 2021 season.
The 31-year-old Bakhtiari, a five-time All-Pro selection, said earlier this month that up to that point he had not strongly considered retirement.
"I think it's going to be more like a doctor having to be like, 'You'd know. What are you doing?'" Bakhtiari said Sept. 20. "And I'd be like, 'All right, fair.' I mean, I'm going to get fined for this one, but I just enjoy it too much and I'm too f---ing good at it. It's just tough for me to... if I was bad, like, when I play games with like one hand tied behind my back and I'm still just like doing my thing. At least if I was bad, I'd maybe entertain it a little more, but that's the part that's tough, when I know I'm still good and at a disadvantage."
The Packers also will be without left guard Elgton Jenkins (knee) against the Lions, but Jenkins told ESPN earlier this week he does not believe a four-game stint on injured reserve will be necessary. Right tackle Zach Tom (knee) also was listed as questionable heading into Thursday night's game.
The Packers signed linebacker Kristian Welch to take Bakhtiari's roster spot. They also elevated cornerbacks Corey Ballentine and Kiondre Thomas from the practice squad for the game because cornerbacks Jaire Alexander (back) and Carrington Valentine (biceps) were both questionable. Alexander was among the Packers' announced inactives.