Wayne Rooney scored twice, Danny Welbeck found the net with a stunning goal, Ashley Young bagged a brace and there was also a double for 20-year-old left-back Reece James as United strolled to victory at the Rose Bowl.
United dominated the match from start to finish and they fully deserved the comprehensive win, which came in front of a crowd of 86,432.
Van Gaal said: "When you see us train, you can expect something but not 7-0.
"It was a surprise, but they were also beautiful goals.
"It was not just the goals, but the beautiful attacks. I never go back, I always want to see the future.
"When I see my team playing a new system, it is better to win 7-0 than to lose because the players will then doubt the system.
"But now I don’t have that problem."
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