Reciting a verse of prostration and forgetting to prostrate

Question

In the congregation of a fard prayer, the imam, while reciting (qira'a), recited a verse requiring sajda al-tilawa, and he performed neither sajda al-tilawa nor sajda al-sahw. Is the prayer valid in this case or not? And supposing such a thing happens, how should the imam perform the prostration?

Answer

When a verse of prostration is recited in the prayer, sajda al-tilawa should be performed within the prayer itself. If he forgot, then, remembering before finishing the prayer, he should perform the prostration and also perform sajda al-sahw. Otherwise there will no longer be any time to make up (qada') this prostration: seeking forgiveness (istighfar)

Source: Fatawa Mahmudiyya

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