Wittgren was optioned to Triple-A Columbus on Sunday, Mandy Bell of MLB.com reports.
Wittgren was acquired from the Marlins in February after being designated for assignment and will somewhat surprisingly start the season at Triple-A. The 27-year-old had a 2.94 ERA, 1.31 WHIP and 31:15 K:BB over 33.2 innings with Miami last season and figures to join the Indians at some point in 2019.