Rooney said that the Dutchman's record speaks for itself and all the players are excited to see what the club can achieve under his guidance in 2014-15.
"He's got a great track record and I'm sure he will come in and do a great job for us," BBC Sport quotes Rooney as saying.
"I don't know how he works, I haven't met him yet but just hearing little things about him, it's exciting for us as a team. This year was not good enough, we need to be fighting for that title."
United finished a disappointing seventh last season.