The Royals plan to insert rookie reliever Nate Adcock into their starting rotation against the Cardinals this weekend. Adcock, 23, was a starter throughout a five-year minor-league career. He is 1-0 with a 2.16 ERA in this season in eight relief appearances. "He deserves an opportunity," manager Ned Yost said, "and he fits the profile of what we're trying to do. He's a young guy with upside. Let's take a look at him."