Tony Allen will miss the rest of the season with two torn ligaments in his left knee.
Coach Doc Rivers said Thursday that Allen will be out at least six months. Allen hurt the knee when he landed awkwardly after an uncontested dunk in the final minutes of a 97-84 loss to Indiana on Wednesday.
Rivers said Allen "was not in good spirits" when he spoke with him earlier Thursday.
"As a coach, you can be emotional, but you still have to function," Rivers said. "He came to believe he could be a great player in this league and now he has to start over again."