Coach Mike McCarthy said after practice that Gardner and Ferguson will be day to day. Manuel said he strained his right calf muscle while working out about about a week-and-a-half ago at his home in Miami. Green and Poppinga are coming off major injuries sustained last season.
Blackmon said he has yet to run since breaking a bone in his right foot during the final practice of the May 19-21 minicamp.
"It's healing up," Blackmon said. "We're just being patient with it right now."
Blackmon was selected with the second of two fourth-round picks by the Packers in the recent NFL draft. He said he is unsure how long he will be sidelined.
"It's frustrating," Blackmon said. "You want to be out there playing. It's my first year in the NFL. I definitely want to get out there. I just have to be patient."
Meanwhile, running back Najeh Davenport and offensive tackle Chad Clifton, who both missed the team's off-season practices, returned. Davenport, coming off a broken ankle sustained last season, took a few reps at running back.
"I never realized I was going to miss football as much as I did until I couldn't play it anymore," Davenport said. "After spending five months on the sideline, I missed it so much, and it felt so great to be out there."
Clifton, who had off-season knee surgery, returned to the left side of the line with the first team.