Lionel Messi is said to have reportedly warned the referee in charge of Barcelona's win over Chelsea: Don't speak badly to me.
The Barcelona playmaker complained to Damir Skomina about a first-half decision which went against the home side.
Skomina said: "Leo, turn it down."
But according to reports, Messi snapped back at the official.
Chelsea felt more aggrieved during the 3-0 defeat when the ref waved away Marcos Alonso's penalty appeal.
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Alonso had gone down under contact from Gerard Pique.
The actual footage shows the Barcelona defender holding his countryman's arm with Alonso through on goal.
Chelsea legend Michael Ballack slammed the referee for the decision to play on.
He tweeted: "Same old story #referee"
