How is the signal for an unnecessary delay indicated by the referee?

The signal for an unnecessary delay is indeed indicated by the referee with an arm bent across the chest while holding a card. This signaling method effectively communicates to players, coaches, and spectators that a delay in the match has occurred, which is important for maintaining the flow of the game. The card serves as a visual representation of the infraction, making it clear that the referee has noted this specific violation.

Holding the card in this manner ensures it is clearly visible to everyone in the vicinity, thus enhancing communication during the match. This practice aligns with officiating standards that emphasize clarity and consistency in signaling various infractions and stoppages within the game.