The Ligue 1 side defeated the North London club 2-1 at Wembley Stadium in their opening Champions League group stage fixture on Wednesday night courtesy of first-half goals from Bernardo Silva and Thomas Lemar.
The Argentine said of his inefficient Spurs: "I think that we all agree that we started well but then we conceded after 15 minutes.
"We cannot concede in that way at this level, in the Premier League, the Champions League. It is difficult to accept how we conceded a goal in this way.
"When you concede like this it is very difficult.
"It is true that we had more chances, our positions, we were better than Monaco but they were more effective."