Mauricio Pochettino conceded Tottenham's Champions League campaign is all but over following Wednesday's 2-2 draw with PSV.
The visitors looked set for a first win in Group B after Lucas Moura and Harry Kane overturned Hirving Lozano's opener in Eindhoven, but Luuk de Jong snatched a late equaliser after Hugo Lloris had been sent off.
The result leaves both Spurs and PSV on one point from three games, five behind Barcelona and Inter.
And Pochettino accepted his side face a huge task if they are to earn a place in the last 16.
"It's nearly, nearly over," he told BT Sport. "We'll see what happens with Barca and Inter. With one point after three games, it's so difficult."
Spurs had a goal from Davinson Sanchez controversially disallowed in the first half before Lucas equalised, while Lloris was given a straight red card for a challenge on Lozano outside the penalty area despite defenders covering nearby.
Pochettino, though, insisted Spurs had only themselves to blame for failing to kill the match when they were in control.
"It's difficult to judge the game," he said. "Many things happened. Sometimes we need to understand that football is how it is. If your responsibilities when you are in a good situation are to kill the game and you don't kill the game, you need to blame yourself.
"We had control, but the most important thing is to score more than your opponent. We were not clinical in front of goal. In the end, [it's] a draw and a minimum possibility to go to the knockout stage.
"It's easy to blame the decision of the referee but I think if we need to blame someone, it's ourselves. With all the circumstances that happened in the game, you must win.
"We were much, much better than them, but the tempo sometimes was so slow and it's a situation we need to think [about] a little bit because in this type of game, if you get to 2-1, you must kill the game, or the opponent is always alive.
"You have the situation with Hugo, maybe unfair, but if you score more goals you are going to win the game. That's why we're disappointed: not with the decision, but with ourselves."
