The Cubs optioned Rucker to Triple-A Iowa on Tuesday, Tony Andracki of Marquee Sports Network reports.
Rucker has yielded 10 earned runs over 8.1 innings across his last four appearances, causing his ERA to balloon from 2.45 to 5.48. He will head to Iowa in order to right the ship, and Hayden Wesneski was recalled to take Rucker's roster spot.