Horford will enter the first unit for Saturday's game against the Clippers, Sean Grande of NBC Sports Boston reports.
Horford will replace Kristaps Porzingis (ankle) in the starting five, a change that will likely stick for the duration of Porzingis' absence. In 17 starts this season, Horford is averaging 9.2 points, 7.5 rebounds and 3.4 assists.