Herrera was a second-half substitute for the 2-1 defeat.
"The good things that I can take from this game is that even though it wasn't our best performance we put them under pressure in the second half," he told MUTV.
"They (City) wanted to finish the game from ten minutes after half-time, so we did some good things but we want to be champions and when you want to be champions you have to play well from the first minute."
Herrera was happy to discuss his own role in the United side, explaining: "I know what the manager wants from me.
"I am an energetic player, I can recover balls for the team, I can share my spirit with my team-mates and that's what I tried to do. I'm going to be there when the manager wants me to play."