It's a big blow for the Celtics, who are facing elimination after being up 3-1 in the series. Tatum appeared to sustain the injury during Game 6 on Thursday, and the issue is severe enough for the superstar forward to miss Saturday's contest. As he did for most of the regular season, Jaylen Brown will be the Celtics' top offensive option, and the Celtics will turn to Derrick White, Payton Pritchard, Sam Hauser, Baylor Scheierman and others to take on larger roles on both ends of the floor without Tatum.