The Argentine was reacting to the disallowing of his overhead kick in added time at the end of the first half, ruled out for a handball by team-mate Cucho Hernandez.
Asked whether the rules are applied differently when Barcelona are involved, Lo Celso sidestepped the question but delivered a pointed reply: "I can talk about the specific incidents I experienced on the pitch. In the end, Cucho's touch may or may not be an offence, but there are a lot of things happening in that incident. There's a rebound, the ball goes up, and there's a challenge for the ball with the head... I really don't know."
He added: "But if it had been Barcelona who scored the goal, would it also have been disallowed for that offence? I don't know the truth, but what I'm saying is that there's a header challenge and a lot of things happen in a match."
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