Dought & clear, - If a latecomer catches up with theimaam during rukoo’ (bowing).

If a person catches up with the imaam during rukoo', will the rak'ah
count for him?
Praise be to Allaah.
If the latecomer catches up with the imaam in rukoo', our companions said:
If the person can say 'Allaahu akbar' and bow with a pause before he
stands up again, then the rak'ah counts for him, but if there is no
time to pause before the imaam stands up again, it does not count. If
he is not sure, does the rak'ah count? There are two opinions on this,
the more correct of which is:
It does not count, because what is more likely is that he did not
catch up with the imaam. So he has to do the prostration of
forgetfulness (sajdat al-sahw) at the end of the rak'ah that he does
after the imaam says the salaam, because he is doing a rak'ah on his
own and is not sure whether this is an extra rak'ah or not. This is
like the one who is not sure whether he has prayed three or four
rak'ahs: he should do another rak'ah then dosajdat al-sahw. One of
those who discussed this issue was al-Ghazaali inal-Fatawa.It is a
good issue to discuss, because a lot of people have this problem and
most people do not know the answer, so this information should be
passed on. And Allaah knows best.
From Fatawa al-Imaam al-Nawawi, p. 50.