The Vikings will presumably go with Case Keenum, who started the three games Bradford missed and relieved Bradford on Monday night, again on Sunday.
Starting guard Nick Easton will also miss Sunday's game.
The Minnesota Vikings are going to be a couple of key players short for their first meeting with the Green Bay Packers this year. For a team that has already lost promising rookie running back Dalvin Cook for the season with a torn ACL, the uncertainty only increases.
With a career completion rate of 58.4 percent entering 2017, Keenum isn't an ideal option to lead Minnesota's air attack, but the Vikings at least know what to expect from him should Bradford be forced to miss extended time.
Bradford aggravated a left knee injury in Monday's win over Chicago that has plagued him since the season opener.
In his absence, Case Keenum will start his fourth game of the year.
Diggs, meanwhile, sustained a groin injury in the Chicago game and finished with just one catch for 4 yards.