Borussia Dortmund manager Jurgen Klopp has described his side's 4-1 win over Real Madrid in the Champions League semi-finals as "unbelievably great".

Robert Lewandowski netted all four of Dortmund's goals at the Westfalenstadion on Wednesday as the Germans earned themselves a significant first-leg advantage over their Spanish opponents.

"It was an unbelievably great game from my team and it was so difficult to play against Real Madrid because they are so strong and fast and counter-attack so brilliantly," Klopp told Sky Sports News.

Dortmund travel to the Santiago Bernabeu for the second leg on Tuesday.