Manchester United lost the first leg of their last 16 clashes 2-0 against PSG.
Red Devil legend Rio Ferdinand reckons United should concentrate on finishing in the top four after they were left with a Champions League mountain to climb.
Speaking on BT Sport, he said: "They’ve got to think about going forward and think about finishing in the top four. This game, this tie is over after the red card."
Ferdinand admits United will struggle to fill the void.
He added: "That's a sign of how far he’s come in the last couple of months.
"Now he’s being man-marked on the biggest stage by Marquinhos. Then he’s really got to show his quality, how do you deal with being man-marked. Today he didn’t work it out and got frustrated and sent off. But more of that is going to come from Pogba because of what he’s doing on a weekly basis in the Premier League."