Tuesday is an off-day for the Major League team.
Minor Leaguer Chris Anderson will start Monday's Major League game.
Mattingly said McCarthy requested the switch so he could work on pitches and have better control over getting up and down between innings.
Mattingly wasn't sure who would start on Wednesday, but Clayton Kershaw would start Thursday and Zack Greinke's turn is Friday.
Ken Gurnick is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.