Former referee, Luca Marelli, commented on Marco Serra's mistake during Milan-Spezia, who disallowed the goal of Junior Messias after not giving an advantage in that action.
Here are Marelli's words to DAZN:
"He was hasty. These are mistakes that can happen to referees who do not have great experience like Serra. The mistake is serious, so much so that he apologized and took his hand to the headset hoping that the whistle had come after the ball had crossed the goal line."
Referee’s mistake costs AC Milan 3 points against Spezia – Review and players ratings