However, the Dutch boss dropped captain Harry Maguire and Cristiano Ronaldo and was fully vindicated as his side gave a rousing display to merit a 2-1 victory.
“I wanted a different approach, a different attitude,” said Ten Hag.
“That is what they bring on the pitch, that is what makes me satisfied,” added the United boss. “We can talk about tactical, but it is all about attitude.
“Now you see we bring attitude on the pitch and there was communication, there was a fighting spirit and there was a team – and you can see what they can achieve because they can play good football.
“It is just the start, we have to keep humble, we can play a lot better if we keep more composure. We have good players – now be a good team and then we will act.
“It is not always about what we said, I said we had to act and not talk a lot, make sure you are a team, battle and also be brave.”
Speaking on Sky Sports, former Manchester United captains Roy Keane and Gary Neville were both enthused by the performance of Ten Hag’s side, having previously been highly critical.
“What we have seen, we haven’t seen for 12 months. I’m absolutely stunned – I did not think that was possible,” said Neville.
“Fans want heart, passion and running. They want the players out there to care and those Manchester Utd players have done it and wow have they needed it, because it has been bad in the last seven to 10 days.
“That can’t be a one off, everyone has seen what they can do. They have set themselves a standard.”
Keane added: “Before the game the manager made some huge calls and the players responded. The players played with great commitment and desire. They were outstanding. You hope this is lift-off for the Ten Hag era.”
Maguire and Ronaldo remain leaders
Having been outfought and outplayed in their opening two games, included the humiliating 4-0 reverse to Brentford, United came into the contest against their old rivals without a Premier League point and seeking to avoid five consecutive league defeats for the first time in 50 years.
And they were dynamic and aggressive from the start as Marcus Rashford took up a central striking role in place of Ronaldo and Raphael Varane partnered the outstanding Lisandro Martinez in central defence in place of Maguire.
Another uplifting moment for Ten Hag and his squad also saw new signing Casemiro paraded in front of the Old Trafford crowd prior to kick-off.
“We were talking about leadership, today we had leadership on the pitch, he is one as well,” added Ten Hag of the Brazil midfielder. “He knows the game, he knows how to win. In his career he has won so many trophies and it is important to have that in the team.
“Varane has it, Casemiro is another one, Ronaldo has it, so you need some and it is like guidance for young players who didn’t achieve the trophies.
“That is what we want to achieve, so I am hoping their presence will be a huge stimulation for the rest.
“I don’t have to mention Harry Maguire and Ronaldo, they are amazing players and they will play a role in the future, the short (term) future as well.
“It is always difficult (to leave them out) but I have decisions to make.”