Michel Carrick's team lost their opening summer game 1-0 to Wrexham, but they bounced back in impressive style, as he rotated once more with goals from Shea Lacey, Joshua Zirkzee, Jacob Devaney, Harry Amass and Ethan Williams.
Most players got 45 minutes, as Carrick continues to assess his options within a limited squad, with several key names still away on their summer break.
Player union rules mean a minimum three-week gap must be adhered to from each player's end date at the 2026 FIFA World Cup and their return to preseason to ensure adequate rest.
Marcus Rashford and Kobbie Mainoo will be the last players back - due to join up with Carrick's squad as part of the Ireland leg of the summer tour - and the United boss was keen to stress the need for patience with his emerging youngsters.
"I think we're in a good place. There's four weeks to go until the start and we're gradually getting some boys back from the World Cup.
"I think a little bit of patience and time and trying to keep ahead, and as I say, keeping everyone fit."
United are next in action on August 1st when they face Atletico Madrid in Stockholm.