Rucker (toe) began a minor-league rehab assignment at Triple-A Iowa on Saturday, striking out one over a scoreless inning while working around a hit and a walk.
Rucker has been on the shelf since May 19 due to a bout with turf toe, but he looks on track to return when he's first eligible or shortly thereafter. It's unclear if the Cubs plan on having him make another tune-up appearance in the minors prior to being activated.