Celtics injury updates: Marcus Smart upgraded to probable, Al Horford doubtful, Derrick White out for Game 2 | CBS Sports Headlines Celtics injury updates: Marcus Smart upgraded to probable, Al Horford doubtful, Derrick White out for Game 2 Smart has a sprained right foot, and Horford is in health and … Continue reading Celtics injury updates: Marcus Smart upgraded to probable, Al Horford doubtful, Derrick White out for Game 2