The Reds’ captain thought he had scored with a powerful header past Gianluigi Donnarumma, only for celebrations to be cut short when Andy Robertson was judged offside and deemed to have interfered with play.
“I think it's obvious and clear that the wrong decision has been made, at least in my opinion. Because he (Robertson) didn't interfere at all with what the goalkeeper could do,” Slot told Sky Sports.
“Immediately after the game someone showed me the goal that the same referee allowed City against Wolves last season (John Stones’ last minute winner). So, it took the linesman 13 seconds to raise his flag to say it's offside. So, there was clearly communication.
“That could have influenced the game in a positive way for us because in the first half we were so poor.
“We would have been lucky going 1-0 down at half-time, let alone if it was 1-1 or 2-1 down. So it has been an influential decision, which is not to say that we then would have had a result over here because you cannot predict how the second half would have gone.”