Lucien Favre felt Borussia Dortmund panicked after falling behind against Tottenham and were heavily punished for their lack of focus in the Champions League at Wembley.
Bundesliga leaders Dortmund impressed in the opening 45 minutes of their European last-16 tie away to Tottenham, but they wasted numerous chances in a 3-0 first-leg loss in London.
Having been in a position of strength at the break, Dortmund's night quickly unravelled as Tottenham upped the tempo after the restart on Wednesday.
Son Heung-min gave Spurs the lead before late strikes from Jan Vertonghen and Fernando Llorente sealed victory for the Premier League team.
"We played well in the first half, we had a couple of chances," head coach Favre told reporters at his post-match media conference. "We defended really well and played well going forward.
"In the start of the second half we gave it away. When we lost the ball and the cross came straight in and was in the back of the net. It was a gift.
"After that we tried to play a bit too hastily and it was very, very difficult for us.
"Sometimes we just had to defend. The second goal we’ve got to move the ball and after the second goal it was harder to hold on to the ball and create chances."
Jadon Sancho had been a shining light as Dortmund started well, but his return to London ended in disappointment. However, the England international is not giving up just yet.
"I don't have any words for the second half," the 18-year-old told BT Sport. "We tried our best but Tottenham scored and were the better team.
"In the first half we played really well. We just dropped a bit and lost focus. In the next game we need to keep focused for the whole game.
"We are still in it, we have to stay focused, we will keep believing we can score more than them and hopefully we can get through to the next round."
Sancho added: "I am just happy that I am in England and playing in front of my family.
"I am happy that I am home and I hope I gave the audience something they never knew about me."
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