The Vikings placed Jefferson (hamstring) on injured reserve Wednesday, ruling him out for the next four games, Craig Peters of the team's official site reports.
Minnesota signed receiver N'Keal Harry off the practice squad in a corresponding move, while the likely beneficiaries in terms of targets are Jordan Addison, K.J. Osborn, Brandon Powell and tight end T.J. Hockenson. The Vikings seem to have hope that Jefferson will ready to play after missing the requisite four games, though it's also possible Minnesota's playoff hopes (or lack thereof) end up affecting the decision a month from now. His earliest possible return date is Nov. 12 against the Saints in Week 10.