The Englishman is one booking away from a one match ban in the Premier League.
If he is suspended, he would miss the league game against Liverpool on Sunday.
But United will not take precautions to sideline Maguire, given his importance to the team.
Maguire has been the United player with the most minutes played this season, which was also the case last term.
"Harry is playing, definitely, that's for sure," manager Ole Gunnar Solskjaer told reporters.
"If he doesn't wake up ill, you cannot only take three points and not put your eyes on games beyond this one."