Horford has missed Boston's past 3 games with concussion-like symptoms after being struck in the head during a workout a week ago
Kevin Love does not take part in practice and Cavaliers coach Tyronn Lue says a decision will be made on Love come game day
Andrew Bogut, who was already wearing a mask to protect a broken nose, suffered a concussion in Golden State's NBA season opener
Klay Thompson passed initial concussion tests after being hit in the head by a flying knee in game 5, but was unable to drive himself home and vomited repeatedly
FIFA announced plans to allow referees to halt matches for up to there minutes so that players suspected of sustaining a concussion can be assessed
New US guidelines advise any athlete suspected of getting a concussion during sports should stop play, leave the game and not return until cleared by a licensed health care professional.
Concussion has become a major concern in American football and ice hockey, as star players are sidelined and former players increasingly speak out about the long-term health effects of head injuries