Head coach Kyle Shanahan said Monday that Kirk (calf) is "unlikely" to return to practice this week, Nick Wagoner of ESPN.com reports.
The 49ers' wide receiver room is even more thin following the team's 32-29 win over the Seahawks on Sunday, when Deebo Samuel left the game due to a hamstring injury. Kirk opened the regular season on IR because of a calf injury that he sustained in late July, and while he has progressed in his recovery, he's not quite ready to return to practice. With both Samuel and Kirk sidelined, the 49ers will turn to one of Brandin Cooks, Jordan Watkins and Jacob Cowing to operate as the WR2 behind Mike Evans.