Rooney hounded Newcastle keeper Tim Krul in the dying moments of the match, forcing the mistake which led to Ashley Young’s winner.
It was a vital three points for United given fellow top four contenders Liverpool, Arsenal and Tottenham Hotspur all won on Wednesday night.
Van Gaal was delighted with the ‘unbelievable’ spirit of Rooney and praised his side’s desire to win even in the last moments of the game.
Speaking about Rooney, van Gaal said: ”I have to say that Wayne, how he makes that goal, is unbelievable, because it was a lost ball. But his fighting spirit is unbelievable.
“I have a fantastic group. They have the spirit and, in spite of all the criticism, they want to win and always play good football. Today I think we played good football.”
Young’s winner was a get out of jail card for United and they were lucky to take away all three points away from the clash.
Papiss Cisse and Ayoze Perez were both denied by fantastic saves from David de Gea while Rooney and Marouane Fellaini spurned good opportunities at the other end. However, two defeats in 22 games is an excellent record and one that United can rightly be proud of.