But the forward, who was selected ahead of Daniel Sturridge, believes Klopp’s side can finish the job against his former club and reach the semi-finals of the Europa League.
“It was a big game,” said Origi. “At a big club you have responsibilities. Everybody tried to help me so I am happy to score.
“It is a huge boost for us to produce a performance like this. It is promising for the next game.”
Klopp – spent seven years as manager at Dortmund – saw Mats Hummels equalise just after half-time, but praised his players’ performance.