The Reds hold a 2-0 lead as they head in to the second-leg of their quarter-final tie against Porto at the Estadio do Dragao.
Ernesto Valverde's side took the lead in the 16th minute via a stunning strike from Lionel Messi, who doubled the advantage just four minutes later.
Former Liverpool midfielder Philippe Coutinho scored after the hour mark with a trademark shot to seal a semi-final place for the Spanish side.
Liverpool will face Barcelona at the Camp Nou for the first-leg on 1st May should they qualify. The return leg will take place at Anfield on 7th or 8th May.
A fixture against Barca is a fascinating prospect for Liverpool, who will welcome back former players Coutinho and Luis Suarez for the first time since their departures from Anfield.
Meanwhile Ajax are the other team through to the semi-finals after beating Juventus 3-2 on aggregate with a 2-1 victory in Turin. The Dutch side will face either Tottenham or Man City in the other semi-final.
Whilst all focus is on the Premier League for now, the hope is that Liverpool can also replicate last season's Champions League run which saw them reach the final in Kiev.