Tottenham edged out Liverpool in a controversial finale to their Carabao Cup semi-final first leg.
Lucas Bergvall gave Spurs a narrow advantage to take to Anfield - but Liverpool were left raging that the 18-year-old was on the pitch to make the decisive contribution four minutes from time.
Bergvall was on a yellow card when he caught Liverpool defender Kostas Tsimikas late in an incident not seen by referee Stuart Attwell.
Tsimikas was still off the pitch when Bergvall scored moments later, prompting a furious reaction from head coach Arne Slot, who was cautioned.
Spurs deserved the win after Pedro Porro missed a great chance and Dominic Solanke saw a goal ruled out for offside, but the manner of their win will leave a bitter taste for Liverpool, who suffered only their second defeat under Slot.
Liverpool came closest when substitute Trent Alexander-Arnold's shot was cleared off the line by Radu Dragusin, but this was a very disappointing display by the Premier League leaders.
And the victory for Postecoglou's side, who were already without 10 players through injury and illness, came after they lost Rodrigo Bentancur amid worrying scenes early on. He went down in the penalty area and was taken off on a stretcher wearing a neck brace after 10 minutes of treatment.
It was later confirmed he was conscious, talking and would undergo further checks in hospital.
BBC