Louis van Gaal declared that he was enchanted with the maneuver his players had adapted to his new opening system after his reign at Manchester United began with a vigorous victory over LA Galaxy before 80,000 spectators and supporters at the Rose Bowl, Pasadena.

He ran out comfortable victors against a side featuring former Tottenham Hotspur forward Robbie Keane and Landon Donovan, once of Everton, thanks to double-strikes from Wayne Rooney, Ashley Young and Academy graduate Reece James and a fine opening goal by Danny Welbeck.

The 13-time Barclays Premier League champions proved his strength in this kind of sports once more.

Van Gaal grabbed a strong starting XI which was deployed in a 3-5-2 formation featuring Chris Smalling, Jonny Evans and Phil Jones protecting David De Gea, with Antonio Valencia and Luke Shaw, summer signing, as wing-backs. There was also a debut in midfield for Ander Herrera, who excelled on his first outing, alongside captain for the night Darren Fletcher and Juan Mata, in a more complex role.

Rooney and Welbeck merged well up front, with the latter opening the scoring with a 25-yard strike in off the post on 13 minutes and Rooney scoring from the spot and from close range before the interval.

Van Gaal made several substitutions at half-time, with James taking full advantage of his first-team opportunity with a couple of goals before fellow half-time substitute Young followed suit with a late brace, and the Dutchman was clearly satisfied with his team's display.

"It is fantastic how they have performed today," Van Gaal told www.manutd.com. "When you see us train, you can expect something but not 7-0. It was a surprise, but they were beautiful goals and beautiful attacks."

He added: "The result always matters. With such a result you get confidence. We introduced a new system and played twice on the training pitch, 11 v 11. It is not very much, but the boys are willing to pick up the information."

"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."

Man Utd first-half XI: David de Gea; Phil Jones, Chris Smalling, Jonny Evans; Luke Shaw, Darren Fletcher, Ander Herrera, Juan Mata, Antonio Valencia; Wayne Rooney, Danny Welbeck

Man Utd second-half XI: Anders Lingaard; Rafael, Tyler Blackett, Michael Keane; Nani, Darren Fletcher, Ander Herrera, Reece James; Luke Young; Shinji Kagawa

Goals: Welbeck, Rooney 2, James 2, Young 2

(Source: Barclays Premier League official website)