Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) narrates that the Noble Prophet (peace and blessings be upon him) said: "When a person forgets a prayer and then remembers it while he is performing another prayer, he should first complete his current prayer, and when he finishes it, then he should perform the prayer which he had forgotten."

Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) narrates: "When a person forgets a prayer and then remembers it while he is following the imam, he should perform the prayer with the imam. When he finishes that prayer, then he should perform the prayer which he had forgotten. Then he should repeat the prayer which he performed with the imam."

Some narrators have transmitted it as a marfu‘ (attributed to the Prophet) hadith, but those narrators were mistaken in this regard.