The Twins placed Wallner on the 10-day injured list Wednesday with a left oblique strain, Bobby Nightengale of the Minneapolis Star Tribune reports.
Wallner is absent from the lineup for Tuesday's game versus the Marlins.
Wallner is out of the lineup for Monday's game against the Guardians.
Wallner went 1-for-3 with a solo home run and a walk in Thursday's 4-3 win over the Rays.
Wallner is absent from the lineup in Tuesday's game in Tampa Bay.
Wallner isn't in the Twins' lineup for Tuesday's game versus San Diego.
Wallner isn't in the Twins' lineup for Thursday's game versus Texas.
Wallner is out of the lineup for Wednesday's game against the Royals.
Wallner is absent from the lineup for the first game of Friday's doubleheader against the Guardians.
Wallner will serve as the Twins' designated hitter and cleanup batter in Wednesday's game against the Cubs.