Bulls forward Tyrus Thomas left the team's preseason victory over the Pacers on Friday night with a concussion.
Chicago used a 34-19 advantage in the third quarter to beat Indiana in what was just the second preseason game for the NBA's replacement officials.
Thomas left the contest in the third period.
Rookie Taj Gibson led the Bulls with 19 points and 9 rebounds, while Indiana's Danny Granger led all scorers with 27 points.
"Taj is like the Energizer Bunny, just keeps on coming at ya," Bulls coach Vinny Del Negro said. "He shoots it better than you think, he's picking and popping, he's long. Just a great effort for a first game for a rookie. It's a good sign for him."