Cubs activate Welington Castillo
Castillo was sidelined with a rib cage injury and recently wrapped up a two-game rehab assignment with Triple-A Iowa. Castillo is batting .242 with five home runs in 43 games with the Cubs this season.
Veteran catcher Eli Whiteside was designated for assignment to make room for Castillo on the roster. The team expressed optimism that Whiteside would be retained and optioned to Iowa.