Johnson is out for Thursday's game against the Rockets due to left calf tightness, Brad Rowland of the Locked On Podcast Network reports.
After playing 33 minutes during Wednesday's 117-106 victory over Boston, the star forward is sitting out the second half of this back-to-back. With Onyeka Okongwu (face) also ruled out, the Hawks are likely to ask more of Corey Kispert, Luke Kennard and Mouhamed Gueye in the frontcourt Thursday.