Prayer: Is the Prayer Valid if One Misses the Required Tashahhud After Joining in the Second Rak‘ah?

Practical Laws of Islam as per the teachings of Imam Khamenei

Prayer: Is the Prayer Valid if One Misses the Required Tashahhud After Joining in the Second Rak‘ah?

English:

Question #570:

An individual arrives at a masjid when the congregational prayer is in its second rak‘ah. Due to his ignorance of Islamic rules, he does not perform the tashahhud obligatory for him in the following rak‘ah. Is his prayer correct or not?

Answer #570:

The prayer is correct but he should, by obligatory caution, perform the qaḍā’ of tashahhud. He should also perform the two prostrations of inadvertence as he failed to perform the tashahhud. However, it is an obligatory caution that he makes the qaḍā’ of the forgotten tashahhud before performing the two prostrations of inadvertence.

-Imam Khamenei, Practical Laws of Islam, Importance and Conditions of Prayer