Ryan was optioned to Triple-A Iowa on Friday, Gordon Wittenmyer of NBC Sports Chicago reports.
The 29-year-old made 18 appearances out of the bullpen for Chicago last season and posted a 5.17 ERA, 1.40 WHIP and 11:6 K:BB over 15.2 innings, and he'll open 2021 in the minors. Ryan figures to return to the majors at some point this season.