United won 2-1 as substitute Scott McTominay headed home in injury-time.
Ten Hag said: “It was massive. It's a massive win for us. So, we get closer. And that was the aim for today and was absolutely our target. And we did it. And I think also the way we did it, I think I liked it, and of course, I liked especially the first 20 minutes.
"And when we are dictating the game, after I think we are dropping a little bit too much. We had our moments in the counter attacks, but yeah, I think then at 1-1, to fight back, we are really happy for today."
“In that moment, you always have to to see how a game progresses. And I think it was really high intensity and you could see how many players were so, so fatigued by the end. It was so open and it could go two ways. But then finally, I think we found the mentality, the character to win this game. And I think also the subs, they have had an impact.
“[It meant] Bruno could become more of a midfielder then in the offensive. I understand the players see the spaces and go for goal in such moments because they are offensive, they want to score goals. But I think it was better in certain situations to keep the ball and let the opponent run, drag them out and then it will open up. And so that was more the idea to bring an extra midfielder there. But with Scott, you have a player who can score a goal."