Quarterback Sam Bradford and three other Vikings starters were unable to practice again Thursday.

Bradford, who was pulled from Monday night's game after re-aggravating his injured left knee, appears to be a longshot to play Sunday against the Packers after sitting out a consecutive day.

Case Keenum led quarterback drills Thursday during the 15 minutes of practice open to reporters.

One starter, defensive tackle Tom Johnson, was able to return to practice Thursday after sitting out Wednesday due to a knee injury. He had his helmet and warmed up with teammates at the start of practice.

Three other starters, receiver Stefon Diggs (groin), left guard Nick Easton (calf) and safety Andrew Sendejo (groin), were held out again. Reserve lineman Jeremiah Sirles is in line to start at left guard should Easton be unavailable against the Packers.

Diggs said this groin injury is not as severe as the strained groin that hampered him early last season, holding him out of one game. But he still wasn't able to practice Thursday.

"It's not the same way as last year. Last year was pretty bad," Diggs said. "I feel pretty good."

Linebacker Eric Kendricks was limited again Thursday due to a shoulder injury he suffered in Chicago.

For the Packers: CB Kevin King (concussion), S Morgan Burnett (hamstring), LB Ahmad Brooks (back) and LB Joe Thomas (ankle) did not practice on Thursday. OT David Bakhtiari (hamstring), OT Bryan Bulaga (ankle) and CB Davon House (quad) were limited.