The follower going into ruku' after the imam has raised his head from ruku'
Question
Question: in a place where there are very many people at the prayer, a man came and joined the prayer; the imam had [already] risen from ruku', and the man did not realise it. Did this man catch the prayer [this rak'a] or not?
Answer
If it is established that the person joined the prayer after the imam had risen from ruku', then he did not catch that rak'a; if he did not pray it afterwards, his prayer is not valid.
Source: Fatawa Mahmudiyya
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