Marcus Smart's career-long 3-point struggles are well-chronicled, but his confident shooting in the postseason has provided a huge lift for Boston.
Kelly Olynyk will start in his place.
Stevens said he's uncertain if Johnson will play at all Tuesday night due to the injury.
Johnson injured his shoulder in the opening minutes of Sunday's Game 3 when he got tangled with Cleveland's Tristan Thompson while chasing a rebound. Johnson later returned to the game but did not practice on Monday.
Even as a starter, Johnson's playing time has been limited this postseason. He is averaging 2.7 points and 2.1 rebounds over 10.5 minutes per game in 13 appearances, including nine starts.
This will be Olynyk's first playoff start of his career. He started six regular-season games this season in 75 appearances.