The Americans were full of confidence having thumped Tus Altenberge 6-0 in their opening game and, for 20 minutes, they matched the Reds in front of an appreciative crowd at the Showgrounds in Coleraine. But the game turned on two pieces of magic by Andreas Pereira, first his through ball allowed Joe Riley a clear run on goal and he rounded the keeper before rolling into an empty net.
Then, in the second half, the Belgian curled home a wonderful free-kick from wide on the left touchline to double the lead.
United were good value for the win and could have added more goals with a fluent second-half display. Ruairi Croskery smashed a drive against a post and Demetri Mitchell was unlucky to see his lob drop wide. The Reds are back in action on Wednesday night against Tus Altenberge in the final group game.
United: J.Pereira; Reid, Tuanzebe, Borthwick-Jackson, Thompson; Riley, Willock (McTominay 61), A.Pereira, Mitchell; Croskery, McBurney (Rashford 50).