Gray (concussion) did not practice Wednesday, Jim Wyatt of the Titans' official site reports.
Gray was concussed in the fourth quarter of last Sunday's loss to the 49ers and is in danger of missing his first game of the season. The 23-year-old linebacker has started all 14 games, posting a whopping 144 tackles (85 solo), including 1.0 sacks, four pass breakups and a pair of fumble recoveries on 90 percent of the defensive snaps. James Williams would likely be in line for increased reps if Gray is unable to face the Chiefs on Sunday.