Marisnick sustained a UCL injury in his left thumb and will require surgery, Jake Crouse of MLB.com reports.
Marisnick landed on the injured list Tuesday after sustaining his thumb injury during Monday's matchup against the Dodgers. The 31-year-old doesn't have a timetable for his return, but he'll presumably require more than the minimum of 10 days on the IL. Prior to his injury, Marisnick had hit .163 with two doubles, five runs, an RBI and a stolen base over 22 games.