Cubs pitcher Ryan Dempster is waiting for an apology from Carlos Zambrano for his recent dugout tirade. Zambrano had to be separated from first baseman Derrek Lee after allowing four runs in the first inning against the White Sox on Friday afternoon. He was sent home by manager Lou Piniella, suspended indefinitely by the team and will be put in the bullpen upon his return. "I think that's up to him," Dempster said Monday on "The Waddle & Silvy Show" on ESPN 1000. "When you do those things and react the way he did you have to be the one to stand up and go out there and accept responsibility. I think he will be willing to do that but we'll have to wait and see. I can't make speculations because I don't know what's going to happen. Whatever happens, happens and we're just worried about going out and winning the ball game tonight."