Van Gaal has wasted no time in stamping his authority on the Premier League club after taking over following Netherlands' World Cup campaign, which ended with a third-placed finish.
The wily 62-year-old tactician has adopted a 3-5-2 formation during the tour of the United States and that proved to be a winning formula as they beat Liverpool 3-1 to win the International Champions Cup on Monday.
Rooney took his tally to five goals in three games when he found the back of the net against Brendan Rodgers' side and the England striker is thriving on Van Gaal's no-nonsense style of management.
"It's been a good few weeks, we've got a new manager who wants us to play a different style of football," the England international said.
"We've had to adapt. We’ve had some good results against top opposition so we can be pleased.
"I think the system suits the team, not only myself. The manager came in and had a look at the players we've got. He's done what he thinks is best suited for our team.
"He's a tough manager but he's been great since he came in. He's given us all a different way of looking at football, which we haven't had before. It's been great for us and hopefully that will continue.
"We wanted to win games, play well. And obviously we've done that. We’ve won a trophy as well. It's always nice to beat Liverpool. We're happy with the work we’ve done out here, now we go on to Valencia and then the season starts."
