Gross-Matos (knee) did not practice Wednesday, per the NFL's injury report.
Gross-Matos was activated from injured reserve prior to the 49ers' Week 16 contest against the Colts, which was his first game back from a 10-game absence due to a hamstring injury. However, the sixth-year defensive end is now working through a knee injury, and he would need to practice in full by Friday in order to avoid an injury tag against the Bears on Sunday.