Detroit's leading scorer strained his right elbow in the final seconds of Boston's 106-102 win on Wednesday night. X-rays were negative, and Hamilton's arm was in a sling as he left the arena.
Coach Flip Saunders said Hamilton is scheduled for an evaluation Thursday, but his status won't be determined until Friday when the Pistons host the Celtics in Game 6. Detroit needs a win to extend the Eastern Conference finals.
Hamilton, who scored 25 points, was hurt with 8.2 seconds left and was replaced by Lindsey Hunter with Boston leading 102-101.
"He got a little bit of, I think, hyperextended in there on the rebound on that one defensive sequence that we had," Pistons coach Flip Saunders said after the Celtics took a 3-2 lead in the best-of-seven series. "He was great again tonight, especially in the last three quarters. Hopefully he's going to be ready to go for us."
Hamilton leads the Pistons in the series with 22.2 points per game.