Cubs placed right-handed pitcher Jake Arrieta on unconditional release wavers, the team announced on Thursday.
Arrieta, 35, has struggled this season with a 6.88 ERA and 5-11 record. In the Cubs 10-0 loss at home to the Brewers, Arrieta allowed eight hits against 11 hitters in the first inning.
In Arrieta's first stint with the Cubs from 2013 to 2017, he helped the Cubs snap their 108-year championship drought to win the 2016 World Series. Arrieta also won the National League Cy Young Award in 2015.
Arrieta has a career 3.93 ERA and 1,424 strikeouts in more than 1,600 innings pitched.