It was the Bulls' eighth loss in their last nine games.
"I don't worry about that. I really don't," Del Negro said. "I go to work every day, doing the best and trying to develop these guys. Those are questions for [general manager] Gar [Forman], [team president John Paxson] and [owner] Jerry Reinsdorf.
"Were fighting with what we have. Well keep on fighting. And those decisions aren't up to me."