Neymar and his team-mates were totally outclassed on Tuesday night, as Paris Saint-Germain won the first leg 4-0.
No team has ever come back from a four-goal deficit in the Champions League and the Brazilian admits it will be tough at the Camp Nou on March 8.
“Now we have to think about the return match and see what we can try to do to reverse this situation,” Neymar told journalists.
“But it will be very difficult, practically impossible. However, we can’t give up.
“All credit to PSG. This match was atypical, we are not in the habit of finding ourselves in this sort of situation.
“It will be very difficult to prepare for the return match, with a four-goal deficit. I don’t think this has ever happened to me”, he said.