The League One Lions had beaten AFC Bournemouth, Watford and Leicester City to get to the final eight of the Cup, which prompted Pochettino to take a cautious approach into the meeting at White Hart Lane.
"It was a game we took very seriously," he said.
"We knew it would be a difficult game because they beat three Premier League teams and we were aware about that. But we played very well, we were very focused, we gave our best on the pitch.
"I think we did well. I'm very pleased, very happy to be in the semi-final and play again at Wembley."