Celtics notebook: Gordon Hayward in concussion protocol, still
Celtics notebook: Al Horford shows unusually foul mood vs. Heat
Al Horford - Wikipedia
Former Gator Horford Continues to Sit with Concussion - ESPN 98.1
Celtics Notebook: Jae Crowder, Al Horford out with injuries
Al Horford has been a godsend for the Celtics already
Al Horford Placed In NBA's Concussion Protocol, Will Miss
Al Horford Out, Avery Bradley and Marcus Smart in vs. Bulls
Al Horford enters NBA concussion protocol, out vs. Lakers
Concussion was an ordeal for Al Horford - The Boston Globe
Celtics edge Raptors without Kyrie Irving for 12th straight win
Daniel Theis lost for season as Celtics suddenly dealing with slew
Embiid scores 41, 76ers beat Celtics 108-103
Mailbag: Are the Celtics getting their money's worth out of Al