Anthony Martial took his Red Devils tally to three in as many games, while Juan Mata ultimately grabbed the winner after a brace from Graziano Pelle.
English clubs typically struggle immediately after European excursions but the United players, after succumbing to PSV in midweek, left their manager highly satisfied with their performance.
“I had to change my players because of tiredness and tightness and that’s a pity,” said the Dutchman.
“But you know that when you see Champions League clubs they are losing after Wednesday matches. Not many clubs have won.
“The tightness of the Champions League match plays a part in the last 15 minutes, but we could have scored a lot more goals.”
The win sees United move up to second in the Premier League table, just four points behind runaway leaders and arch rivals Manchester City.