Young injured his left leg in multiple places in Monday night's 30-3 victory over the Jacksonville Jaguars and was replaced by backup Kerry Collins, who finished the game.
NFL Network's Albert Breer, citing a league source, reports that after missing Friday's practice, the Titans would be "surprised" if Young is ready to go Sunday. Breer said the quarterback remains day-to-day with ankle and knee sprains. There is no structural damage, but the Titans are taking a cautious approach.
Collins practiced Thursday and Friday after banging the middle finger of his right (throwing) hand on a helmet or opponent's hand in the third quarter. The 16th-year veteran is listed as probable and said Thursday that he will be ready to start if Young cannot, noting that he jammed a finger in an opener while with the Oakland Raiders and played with it the entire season.
The Associated Press contributed to this report.