Marcus Smart will undergo surgery to repair a torn ligament in his right thumb.
The Celtics hope Smart could return within six weeks and participate in the playoffs.
Smart suffered what the team initially termed a sprained right thumb while diving to the floor during the first half of a loss to the Indiana Pacers on Sunday. He had the thumb taped and finished the game, after which he downplayed the severity of the injury.
Smart missed 11 games after punching a glass picture frame in Los Angeles in January
Smart will be a restricted free agent this offseason.
