Celtics guard Marcus Smart (ankle) ruled out for Game 4 vs. Heat

Down 2-1, the Celtics look to bring more energy against the Heat in Game 4.

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Celtics guard Marcus Smart has been ruled out for Game 4 of the Eastern Conference finals (8:30 ET, ABC) with a sprained right ankle.

Smart, the reigning Kia Defensive Player of the Year, suffered the injury in Miami’s 109-103 victory in Game 3 on Saturday. Though Smart was able to return and finish the game, Celtics coach Ime Ukoda said the ankle swelled up in the ensuing days despite aggressive treatment.

“Pretty swollen,” Udoka told the media before tipoff. “He’s a guy that plays through a lot … it is quite swollen.”

The Celtics also announced that All-Star forward Jayson Tatum (neck) and center Robert Williams III (knee) are both available.

#NEBHInjuryReport update:

Marcus Smart (right ankle sprain) – OUTJayson Tatum – AVAILABLE

Robert Williams – AVAILABLE