Yorke said that United fans should not expect the Dutchman to stay for the long term, but while he was there he would ensure that the players give their all for the cause, which should lead to success.
"He's a man who's very assertive," Yorke told Sky Sports News. "He was very decisive in what he had to say. You could see he's a man who's been in that position before. He was self assured, assuring everybody out there.
"He hasn't been at [one] football club for very long but when he goes there, neverless he does bring success. He's got huge respect from the players.
"If you look at his body language, look at everything he had to say, you'd certainly think you'd have to bring your 'A' game to this team if you're going to be part of his future going forward."
Yorke played for United between 1998 and 2002.