The two sides were tied at 1-1 following the first leg in Germany, and BVB tore into a two-goal lead after scoring twice inside the first ten minutes.
While Liverpool pulled one back through Divock Origi just after half time, a strike from Marco Reus appeared to have taken Dortmund through to the semi-finals.
However, the Reds never lost their self-belief, and scored twice inside the final 25 minutes of the match to complete an astounding comeback.
Philippe Coutinho, Mamadou Sakho and Dejan Lovren scored the goals to take the Anfield giants through to the final four, following a remarkable effort and a dominant final half an hour.
The Reds managed 21 shots to the visitors’ 12, and also registered over 60 percent possession, however, speaking to Sky Germany after the match [as per Goal], Hummels has refused to give the home side credit.
“When we scored to make it 3-1, we thought we were through,” the captain began.
“We stopped defending aggressively and stopped playing football when they scored the 3-1. Then we suddenly got the jitters. We gave it away,” he continued.
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“Liverpool would never have come back if we would have continued to play our socks off after we scored the 3-1. We should have made the opponent chase the ball.
“Instead we just lost touch too often in defence. We just can’t concede goals like that, that was too easy for them. This defeat is the one that hurts the most this season.”