Prayer: Not Going Back into Rukuʿ or Sajdah
Practical Laws of Islam as per the teachings of Ayatullah Sistani
Ruling 1454
If a person mistakenly raises his head from rukūʿ or sajdah and inadvertently or thinking that he will not be able to join the imam does not go back into rukūʿ or sajdah, his congregational prayer is valid.