The manager says that the win over the Reds is the beginning of a new era.
The attitude and desire of United's players and Ten Hag's tactics had been questioned after the two losses.
The Dutch boss was vindicated as his side gave a rousing display to win the game.
Ten Hag wanted a different approach.
That is what makes me happy, that is what they bring to the table. It's all about attitude, but we can talk about tactically.
There was a fighting spirit, communication, and a team, and you can see what they can achieve because they can play good football.
We can play a lot better if we keep our cool. Now that we have good players, we will act.
"It's not always about what we say, but we have to act and not talk much, make sure you are a team, battle and also be brave."
The performance of Ten Hag's side was praised by two former Manchester United captains.
We have not seen anything for a year. I didn't think that was possible, said Neville.
Fans want to run and have fun. They want the players out there to care and that's why the Manchester United players have done it, because it has been bad in the last few days.
Everyone knows what they can do. They have established a standard.
The manager made a lot of big calls before the game. The players were committed and wanted to play. They were excellent. You hope this is the start of the Ten Hag era.
Having been outfought and outplayed in their opening two games, United were looking to avoid five consecutive league defeats for the first time in 50 years.
They were aggressive and dynamic from the start, with MarcusRashford taking up a central striking role in place ofRonaldo and Raphael Varane partnering Lisandro Martinez in central defence.
Casemiro was paraded in front of the Old Manchester crowd before the game.
"We talked about leadership, today we had leadership on the pitch, he is one as well," said Ten Hag. He knows how to win and he knows how to lose. It's important for him to have the success in the team.
It's like guidance for young players who didn't achieve the trophies if you have it.
I hope their presence will be a huge stimulation for the rest.
They are amazing players and they will play a role in the future as well.
I have decisions to make when it comes to leaving them out.