Willingham is dealing with soreness in a rib cage muscle and won't swing a bat until Tuesday at the earliest, Andy McCullough of the Kansas City Star reports. There's some concern that Willingham might be dealing with an oblique strain, which would likely sideline him even longer than the injury the Royals believe he's currently dealing with. The team's scarce usage of Willingham after acquiring from the Twins on Aug. 11 has been surprising considering the team gave up a pretty good prospect in Jason Adam to acquire him, and his usage will likely only decline from here. Eric Hosmer returned from the DL on Monday to bump Billy Butler back to DH duties, and an ailing Willingham will have little chance at surpassing the latter on the depth chart.