The Chicago Cubs activated right-hander Hayden Wesneski from the 15-day injured list on Friday following his recovery from a right forearm strain.
In a corresponding move, the Cubs designated right-hander Shawn Armstrong for assignment.
Wesneski, 26, last pitched July 19 and is 3-6 with a 3.94 ERA, 21 walks and 58 strikeouts in 61u2154 innings over 25 games (seven starts).
He is 9-13 with a 3.96 ERA, 60 walks and 174 strikeouts in 184 innings over 65 games (22 starts) in parts of three seasons with the Cubs.
Armstrong, 34, was 0-1 for Chicago this season with a 4.