Fernandes drilled home from the edge of the area to snatch victory to lift United’s mood after consecutive 3-0 defeats at the hands of Manchester City and Newcastle.
Afterwards ten Hag praised the way his side dug in to grind out a 1-0 win in the wake of two below-par poor performances.
“I am pleased with it. I am pleased with the spirit of the team and with the way we pressed,” ten Hag said.
“We saw this (added time winners) against Brentford and we have seen it again.
“It is a good resilience. They know what the standards are. This is Manchester United. You have to win every game.
“This week we have not been happy with the standards and today we improved with our standards.
“Every game we have to bring the battle which starts with the right mentality and attitude, to show you are hungry with passion and desire.”
A moment of brilliance from captain Fernandes, criticised by former United players after the midweek Carabao Cup loss against Newcastle, proved enough to steal the points for United and earn his manager’s gratitude.
“He gives energy, he is the example,” said ten Hag.
“You can see with the way that he is pressing, with the way that he is counter-pressing in games and the way he recovers.
“So he is absolutely the example and he’s taking the responsibility all the time on and off the field and he’s taken the responsibility by scoring important goals.
“He always wants to have the ball, he always wants to create and I’m happy.”
Fulham boss Marco Silva admitted the late defeat was difficult to accept and highlighted the mistakes in the lead up to Fernandes’ goal.
A rare misplaced pass from Joao Palhinha in Fulham’s box saw Fernandes punish his countryman with a strike which extended the Cottagers’ Premier League winless run to three.
Silva said: “It is a really difficult one for us to take.
“Defeats are defeats and it feels like the same old story.
“We wanted to be the better team and for much of the game we did it but at this level we cannot be getting punished in the way we did.
“In 10 seconds we made three or four mistakes from three or four different players and it is difficult to understand.
“We win and lose together but the individual decisions we have to take in a certain way because there was no reason to be punished in that moment.
“In 10 seconds we lost emotional control completely.”