3. Be the backbone of the defense
Al Horford should be seen as the backbone of the defense for the Celtics frontcourt this season. He may not be the defender he once was, but a performance like last year will need to be improved upon for the Celtics to not get bullied in the paint.
Over the years, this is another area where time may be catching up to Horford. Missing a third consecutive All-Star selection, his defense during the 2014-15 and 2015-16 seasons was what made him a standout candidate. Between both seasons he carried a 102 and 101 defensive rating, only to fall to a 107 rating last season. Horford has performed at an All-Star caliber level on both sides of the ball throughout the majority of his career.
He is still averaging just under two blocks per game and over a steal per game, which is one area he has remained strong in. Being one of the only returning players this season would be enough pressure for most players to face, but Horford will be looked upon to improve the defense of a largely new team 11 years into his career.