NFL Network's Ian Rapoport reported Monday that Allison was likely to undergo surgery for a "core muscle injury."
Allison has been limited to five games this season. He has 20 receptions for 303 yards and two touchdowns, and his 60.6 receiving yards per game are second on the team behind Davante Adams (91.3).
By going on injured reserve, Allison will miss the rest of the regular season. He'd be eligible to return for the playoffs should the Packers get there. At 3-4-1, Green Bay is 10th in the NFC and third in the NFC North.
Although losing Allison won't help the Packers reach the postseason, rookie wideout Marquez Valdes-Scantling has stepped up in recent weeks. The 2018 fifth-round draft pick caught 15 passes for 317 yards and two touchdowns in his last four starts.
Valdes-Scantling's stock was already climbing and now fantasy football owners can expect him to start the remainder of the year alongside Adams, which sends his value even higher.