We'll get the housekeeping stuff out of the way first. The Cubs are not sending either Starlin Castro or Anthony Rizzo to the minor leagues. Before Sunday's 4-2 loss to the Milwaukee Brewers, manager Dale Sveum was talking about players having to "perform" at the big-league level to stay. When a reporter suggested to Sveum that players such as Castro, Rizzo and veteran Alfonso Soriano aren't guys the Cubs are going to replace, Sveum went back to the theme he sounded most of the weekend, when poor defense played a part in the Cubs getting swept in three games. "You have to perform," Sveum said. "The bottom line is you have to perform. Whether you need more development, you decide all those kinds of things. There is still accountability. "I don't think anything's invincible if you're not performing. That's still the one main ingredient that has to happen to win baseball games." When Sveum was asked again about what options he might have to change things, he said: "Find options. If people keep playing like that, you have to find options. Get people playing time at Triple-A to figure this stuff out." Sveum never said the Cubs specifically were considering sending Castro or Rizzo out, but someone who wanted to infer something like that certainly could, even if it is a stretch.