The hosts go into the game against the Red Devils as heavy underdogs to take the three points, but Phillips believes that his side can cause an upset if they exploit United's weakness.
Although the Red Devils have brought in a host of attacking additions over the summer, there is still a feeling that their defence remains short of the quality required to be Premier League winners and Phillips is plotting to highlight this apparent weakness.
"Their defence certainly isn’t as strong as their attacking options and that’s an area we’ve got to try and exploit and, as striking coach, that falls under my remit," he told Sky Sports.
"As I do every week, no matter who we’re playing, I was in talking to our analysts on Monday, going through videos and looking at how we can get through the United defence – and we’ve got some plans in place.
"We haven’t gone overboard worrying about them too much in training this week, though. We’ve been doing a lot of our regular drills and exercises, such as one-touch finishing – which paid off last week."
Leicester have made an encouraging start to life in the top-flight following their promotion, but this may be their toughest test yet.
Nigel Pearson's side have picked up points against Arsenal and Everton, whilst a win away to Stoke City last weekend is sure to fill them with confidence.
Before the international break this may, therefore, have been a fixture which United were fearing. The Red Devils looked bereft of confidence throughout the opening stages of the season, but a 4-0 demolition of QPR last weekend has meant that there is a buoyancy in their step once again.
Louis van Gaal introduced a number of his new additions to devastating effect in the match, and they will be determined to carry on this fine form this weekend.
Another victory against Leicester is sure to give them even more momentum as they look to chase the front-runners and force themselves back into title contention, but they can expect a tough challenge against one of the early season's surprise packages.