Mattison (illness), whom the Vikings placed on the reserve/COVID-19 list Monday, isn't vaccinated and thus has entered into a 10-day quarantine, making him unavailable for next Monday's game at Chicago, Chris Tomasson of the St. Paul Pioneer Press reports.
Mattison returned to his complementary role out of the backfield last Thursday against the Steelers with Dalvin Cook (shoulder) back in the lineup, taking six carries for 27 yards. With Monday's development, those reps now will trickle down to Kene Nwangwu and Wayne Gallman, who was claimed off waivers Monday. Mattison's next chance to suit up will come Dec. 26 against the Rams.