Horford is not in the Celtics' starting lineup for Friday's game against the Bulls, Justin Turpin of WEEI.com reports.
Horford will come off the bench Friday for the first time this season while Kristaps Porzingis gets the start at center. It's the first time Horford and Porzingis will be available to play together this season, and the former should continue to serve as the Celtics' "sixth starter" when the latter is sidelined. Through 14 regular-season contests, Horford is averaging 10.1 points, 5.4 rebounds and 2.4 assists over 27.9 minutes per game.