Ten Hag admitted he was “annoyed” after the result, which sees his side stay third in the table and they are now 11 points off Arsenal.
The Dutchman said his side were “like a pack of cards with the goals we concede” and they must change their mentality going forward.
“Maybe that will come in the next couple of hours, that we will realise we are in a good position, realise we are in a good development and a good process,” said Ten Hag.
“But in this moment I am annoyed and I also told the players: ‘If you want to win trophies, titles, you have to change our mentality, because it’s not possible that you are in a top game making three such big mistakes where you concede’.
“Then especially the last goal, you have to feel the game. At that point, a point was the maximum.
“Then you have to take the point and you can’t give such a goal away like we did. And on top level, you can’t win trophies.
“It was like a pack of cards with the goals we concede.
“Two starting with a corner and then obviously we make mistakes, we didn’t show the discipline in the rules we have there. Then you concede goals.”
Asked how he changes the mentality, Ten Hag said: “With coaching we change that.
“Already we have seen how the mentality from the players has changed over the last couple of months.
“But we also have to notice today that we still have a way to go to be on top level.
“We were a good team on the pitch, we were leading, and then starting [to] make such mistakes, it’s about that.
“We could have won this game. When you are 1-0 up you give so easy 1-1 away, because when you are 1-0 up, spaces will come with our qualities. We could have benefited from it.
“We had a game in the week and we had some disadvantages, but excuses are not possible at the top level. You have to be in the reality and the reality is that we have to perform.”