Jayson Tatum out for Celtics' pivotal Game 7 vs. 76ers with 'left knee stiffness'

Tatum left Game 6 after playing just 29 minutes

Jayson Tatum will miss Game 7 of the first-round series between the Boston Celtics and Philadelphia 76ers, the Celtics announced. Tatum left Game 6 after 29 minutes of playing time and did not return. He said after the game that he was "just a little stiff," and was not initially worried about his status for Game 7.

However, Tatum popped up on the injury report on Saturday, getting listed as questionable with left knee stiffness. The Celtics have every reason to operate with an abundance of caution regarding Tatum's health. He missed most of this season while recovering from a torn Achilles tendon suffered in last year's postseason. He has been stellar since coming back, but there have been a number of serious injuries lately that started with players playing through smaller ones. Most notably, Tyrese Haliburton tore his Achilles tendon while playing Game 7 of the Finals with a calf injury. The Celtics are operating cautiously, so Tatum is sitting out.

CBS Sports will update this story as it develops