Ruling on sufficing with a single takbir for both the opening and the bowing

The questioner:
May Allah reward you. Honorable Shaykh, this questioner says: What is the ruling on the prayer of one who finds the imam bowing and says a single takbir for the opening?

The Shaykh:
Yes.

The questioner:
May Allah keep you safe. What is the ruling on the prayer of one who finds the imam bowing and says a single takbir for both the opening and the bowing?

The Shaykh:
Yes. The takbir of the opening is necessary; it is a pillar that he performs while standing upright and balanced. Then he descends into the bowing. If he wishes, he says the takbir for the transition; if he does not wish to, he does not say it. The takbir of the opening suffices. They said that the takbir for the transition in this specific case is a recommended practice (sunnah). As for other cases, the takbir for the transition is obligatory among the obligations of the prayer. Yes.