Johnson (1-0) allowed one run on two hits and two walks while striking out six for Triple-A Pawtucket on Tuesday.
It was another strong effort for Johnson who has pitched well enough for the PawSox to earn a spot start at Boston this season. The Red Sox need another starter Thursday to replace Steven Wright (knee) but it wasn't in the cards for Johnson. Instead, the Red Sox are calling on Kyle Kendrick to start Thursday and possibly more if Wright needs more time.