Rooney hoping to impress Van Gaal
Van Gaal has been assessing his players since arriving in Los Angeles on Friday night.
The new United boss wants to streamline his squad by the start of the season, and although it would be a huge shock if he decided to dispense with Rooney, the striker still has a lot to prove to the Dutchman.
After a lacklustre World Cup, Rooney will be determined to show he still has what it takes to cut it at the top level, and he will also be trying to stake his claim for the United captaincy, which is vacant following the departure of Nemanja Vidic.
"We have to go out there and show what we can do and show every day in training what different qualities we have as players and a team," the United striker told MUTV.
"Everyone wants to impress a new manager and that's what we're aiming to do."
Having won league titles in Spain, Holland and Germany, Van Gaal brings with him a reputation as one of the best coaches in the world.
There is feeling of huge respect towards the 62-year-old from his staff, and Rooney has been impressed by the former Barcelona manager in his first few days at the helm.
"It's been good meeting the manager and the new coaching staff. The first couple of training sessions have been good and everyone is looking forward to getting the games under way," Rooney said.
"We've got a new manager with different ideas - we have to train well and listen to what he wants us to do and take that onto the pitch and show him what we can do."
United face the Los Angeles Galaxy on Wednesday before heading to Denver, Washington and Detroit to play Roma, Inter Milan and Real Madrid as part of the International Champions Cup.
Pre-season tours are sometimes seen as frivolous affairs, but Rooney thinks the next fortnight could be crucial to an important season ahead.
"Any player will tell you the most important thing for the season is to get a good pre-season under your belt and that's what we're all trying to do," the 28-year-old added.
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