CHICAGO -- New Chicago Bulls big man Pau Gasol missed practice Tuesday with tightness in his back, but his injury was not deemed to be serious.

The 34-year-old veteran, who was signed as a free agent this offseason, did play 24 minutes as the starting power forward in Monday night’s 110-90 victory over the Denver Nuggets. Gasol had nine points, four rebounds and four blocked shots.

Bulls coach Tom Thibodeau has put his team through a heavy schedule in the preseason, saying he hasn’t been satisfied with the overall performance. Thibodeau expressed concern Tuesday that the regular season is just two weeks away and he doesn’t want his team thinking it can just flip the switch when games count for real.

“I don’t want them to fool themselves,” Thibodeau said. “To me, the big thing is understanding what goes into winning and how you practice and prepare and the work that’s necessary to put into it to get yourself in great shape. You need to prepare yourself to play four games in five days, to play a long season, to have an edge, to understand what goes into winning, why you win and why you lose, to build the proper habits. That’s something you do every day.

“When you shortcut that process -- I’ve been around a long time -- I know it doesn’t work. I’ve tried to make that clear. When you watch film, it tells you a lot. For the team to function well, everyone has to do their part.”

The Bulls have been relatively injury-free in camp, and that includes point guard Derrick Rose, who is trying to return from a second consecutive knee injury.