Rio Ferdinand was left in disbelief after Ibrahima Konate was not sent off for a questionable push on Bradley Barcola.
Liverpool faced Paris Saint-Germain in the first leg of their Champions League last 16 clash at the Parc des Princes on Wednesday.
Barcola then went clean through on goal before hitting the deck under pressure from Konate, leading to penalty appeals from PSG.
Konate made contact with Barcola around the edge of the box, but referee Davide Massa didn't believe the defender make enough contact to foul his opponent.