With Cole Palmer missing the game, the rest of the side appeared to collapse in adversity.
Pochettino told reporters: "No, that is not true because we conceded the first goal, of course, after four minutes and then the players, the team was there, we created some chances. The team was in the game.
"Then we started the second-half and after six or seven minutes we conceded the second goal and yes, after then we can talk maybe in the second-half we showed a lack of capacity to believe it was possible. But in the first 45 minutes, everyone believed and everyone that saw the game, the team was there, fighting to try and draw the game, score and we were in the game.
"The lack of belief, with all the circumstances, that sometimes happens. With the disappointment after Man City, and no time to recover, playing against a team that is playing for the Premier League, full of confidence and with all of our circumstances, it was all negative for the team. That is why we suffer.
"We were capable to beat Everton 6-0 one week before playing a fantastic game. We saw two days ago Everton beating Liverpool 2-0 and we were able to play a fantastic game against Man City but we didn't bring the consistency you need to win the game.
"Maybe I repeat too much but that is the truth, the reality. After we conceded the third goal, it was difficult to manage the situation on the pitch."