Eric Bailly’s first United goal on the stroke of half-time set them on their way before Romelu Lukaku, Paul Pogba and Anthony Martial blitzed Swansea in the final 10 minutes.
After last weekend’s 4-0 season-opener against West Ham this was another powerful message sent out by Jose Mourinho’s side.
Strong and efficient at the back, United shut down opponents woefully short of attacking prowess following the club-record sale of Gylfi Sigurdsson to Everton.
Last season’s top scorer Fernando Llorente also remains absent with a fractured arm sustained on his summer holiday, and Swansea boss Paul Clement is in urgent need of investing the Sigurdsson cash to prevent another flirtation with relegation.