Prayer: Performing an Invalidating Act Between Salam and Making up a Sajdah
Practical Laws of Islam as per the teachings of Ayatullah Sistani
Ruling 1241
If between the salaam of the prayer and making up the sajdah one does something that were he to do it intentionally or inadvertently in prayers it would invalidate the prayer – for example, he turns his back to qibla – the recommended precaution is that after making up the sajdah, he should perform the prayer again.