The Argentine believes that his players were not threatening enough in their 2-1 Champions League defeat to Monaco on Wednesday night.
"I was speaking with my players at half-time," said Pochettino of the match which was played in front of more than 85,000 fans at Wembley.
"I think we needed more control in the centre of midfield, we needed to move Dele Alli up the pitch to be more aggressive.
"It is not new. I think we were better than Monaco, we need to win games, we need to be more aggressive with the ball.
"We need to play the way we are meant to play. They played in a very comfortable position.
"It is a fantastic opportunity, we have worked hard to be here and we need to be better.
"We need to work more on being aggressive, to show we are hungry on the pitch. In the second half I think we started well, but not well enough."