The Boston Celtics say Al Horford and Marcus Smart are both out for Game 1 of the Eastern Conference finals against the Heat on Tuesday night in Miami.
Horford is in the league's health and safety protocols, the team announced.
Smart won't play due to midfoot sprain suffered in Boston's Game 7 win against the Milwaukee Bucks on Sunday.
Smart, the NBA Defensive Player of the Year, had been listed as questionable for the series opener, with coach Ime Udoka saying Monday that the veteran guard's foot was "tender and sore" and that he was set to receive round-the-clock treatment for it before testing it ahead of Tuesday's game.