Maguire went down in the at the Spartak Stadium under minimal contact and also pestered the referee for VAR when Jordan Henderson was head-butted.
It followed heavy criticism from Brazil star Neymar, who theatrically exaggerated a foul to get a player sent off against Mexico.
And Mourinho was critical of both players.
"People are focusing on Neymar, but if it was only Neymar, I'd be happy, but it's not only Neymar," he told Russia Today.