Minnesota Vikings wide receiver Mike Wallace was not at practice on Tuesday, according to Mark Craig of the Star-Tribune. The reason for his absence was not immediately known.

Minnesota's wide receiver unit is in a state of flux, and the Wallace mystery only accentuates the uncertainty. Fellow starter Charles Johnson didn't play last week with a hip injury and is still working his way back. On top of that, Jarius Wright is dealing with a hand injury.

In Week 4 against the Denver Broncos, reserve receivers Stefon Diggs and Adam Thielen combined for 12 catches and 157 yards. The Vikings may need even more out of them moving forward.

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Wallace caught his first touchdown pass as a member of the Vikings last week and led the team with eight receptions. The practice he missed was a light, non-padded outing, according to the Star-Tribune. It was also the team's only practice of the bye week.

Wallace should be back well before the Vikings' matchup with the Kansas City Chiefs in Week 6.

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