The Reds secured their place in the final four with a comfortable 5-1 aggregate victory over the Premier League champions elect.
Goals from Mohamed Salah and Roberto Firmino were enough to send Liverpool through.
Shot-stopper Loris Karius will have expected a busy night at the Etihad Stadium.
But City failed to add to their early goal.
And despite not being on the field of play for a single minute of the two legs, Karius’ backup Mignolet took to social media to celebrate his side’s famous victory.
“A night to remember!!!” he tweeted.
“This journey is not over…
“Enjoy the celebrations, Reds! #YNWA #LFC #UCL
Speaking after the match, former Liverpool defender Stephen Warnock praised his old side for their win.
But the left-back thinks Jurgen Klopp’s men will have been on the end of a severe dressing down from their manager at the interval.
“I feared for Liverpool at the start of the game,” he told BBC 5 Live.
“Terrible start but they showed character.
“Klopp had to have got in to them at half time and told them it wasn’t adequate, wasn’t good enough.
“Manchester City looked jaded, looked tired and Liverpool deserved the win.”
