After thrashing Chelsea 4-0 on the opening day, United had failed to win any of their last three games but took all the points to inflict Leicester's first defeat of the campaign.
Rashford could have got another in the second half, but his wonderful free-kick from 30 yards curled over the wall and onto the angle of crossbar and post.
"They read the game well.
"I've got loads of admiration for Vardy, I think he's my type of centre forward, runs in in behind, harasses and you've got to be spot on with the decision-making, when to stay up, when to drop off, and both of them proved their worth today. There were a couple of races and Harry did well.
"I don't think [the abuse] bothers [Maguire] whatsoever. You've got to be that way and when you play, when you coach, when you manage, we don't get carried away when we win a game that we maybe didn't deserve to win, but we don't get in the dumps when we don't win.
"Because the performances have been miles better than this, and today we just have to accept three points and wake up tomorrow with a smile, have a day off, relax a bit and look forward to next week."