Sajda al-sahw after standing up for a fifth rak‘a

Question

Zayd was praying ‘Asr and, by forgetfulness, stood up in the fourth rak‘a instead of sitting. Then in ruku‘ it occurred to him that he was praying a fifth rak‘a; thinking this, he sat down at that very moment, performed sajda al-sahw and completed the prayer. Is the prayer valid or not?

Answer

The prayer is valid.

Source: Fatawa Mahmudiyya

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