Lancaster-born youngster Scott McTominay featured for the Red Devils, with Preston-born midfielder Luke Mulholland among the opposition ranks.
Twenty-year-old McTominay played the first 45 minutes in Utah ,with Mulholland entering the fray after half-an-hour.
Salt Lake threatened a famous victory after Luis Silva handed them a 23rd-minute lead, but Henrikh Mkhitaryan and Romelu Lukaku responded with goals before half-time.
In a tight second half, United held on to their lead to claim victory, although Mulholland almost equalised in the 73rd minute, but fired off target when well placed.
The 28-year-old – who played junior football for Cadley Boys and spent a season with Lancaster City as a teenager – has spent the past decade Stateside after initially studying for a degree on a football scholarship at Wingate University.
He went on to play for NSC Minnesota Stars and the Tampa Bay Rowdies in the North American Soccer League, before landing a dream move to Real Salt Lake in the MLS three years ago.
During his stint in the US, he has since come up against world renowned stars such as Steven Gerrard, Kaka and Thierry Henry.
For McTominay, it was his first taste of pre-season action as he bids to establish himself in the first-team set-up.
Jose Mourinho thrust the Old Trafford academy graduate into the side as last season came to a frantic conclusion, with the 20-year-old making his debut off the bench at Arsenal before starting the Premier League finale against Crystal Palace.
“Obviously it is an amazing experience for me, coming away with the first team on my first tour,” the midfielder said.
“You have got to grasp the opportunity and take everything in, what the players do, how they rest, preparing for games.
“It is just really good to be around the squad and hopefully I can show everybody, including the manager, what I am capable of and push on from there.”