Everything is to play for in the second leg of the Europa League Quarter Final after the reds and Dortmund played out a 1-1 draw at the Westfalenstadion.
Divock Origi struck first with a goal in the 36th minute, and could have had a second on the stroke of half time but his chance was saved by Weidenfeller.
Dortmund hit back early in the second half - their captain Hummels getting time and space to head past Mignolet from a cross.
The reds equipped themselves well in a classic European performance and both sides could have added more goals to the tally.
The early news was, as expected, that Divock Origi was chosen ahead of Daniel Sturridge to start. Firmino was named on the bench, but not fit enough to start.
The game started with both sides utilising their 'gegenpressing' abilities. Reus saw a shot deflected wide whilst at the other end it was Dejan Lovren who had Liverpool's first chance. His header into the ground bouncing up straight towards the keeper.
Aubameyang was having a quieter night - his key first half moment coming when Mignolet dwelled with the ball at his feet - but the Dortmund striker was unable to punish the forward.
Origi's shot in the 36th minute took a deflection to beat the keeper but he was off - celebrating an unexpected Liverpool lead.
Hummels goal early in the second half could have spelled doom - but it sparked a mini reds revival - Joe Allen had replaced an injured Henderson at half time and he was key to some of the reds moves.
As the half wore on Dortmund looked the more likely to score again - Liverpool wasteful at times with the ball and inviting pressure on.
However the reds saw the game out without conceding again.
Jurgen Klopp celebrated Origi's first half goal with a chest pump - and at the final whistle he took time to shake hands with many of his former players.
Liverpool will be the more pleased of the two sides after getting what could be an important away goal - although with the attacking talent at Dortmund's disposal they will be hunting for goals at Anfield.
The return match is in a week's time at Anfield.