Verbal Flag Down Signal

Does the official always have to say "flag-down" or is the slow whistle situation the only time that verbal signal occurs?
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Phantanimal wrote:Does the official always have to say "flag-down" or is the slow whistle situation the only time that verbal signal occurs?
NCAA Rule 7-8 wrote:If a defending player commits a foul against an attacking player and an attacking player has possession of the ball, the official must drop a signal flag, make the verbal signal “flag-down” and withhold his whistle until:
Phantanimal wrote:I understand play on... I just wanted someone to clarify that the slow-whistle is the only situation where the official says flag-down.