"Whoever catches up with one Rak'ah of 'Asr prayer before the sun sets, or catches up with one Rak'ah of Fajr before the sun rises, has caught it."
Sunan an-Nasa'i Book 6, Hadith 22
← Previous Hadith "Whoever catches up with two Rak'ahs of 'Asr prayer before the sun sets, or one Rak'ah of the Subh prayer before the sun rises, has caught it."

Sunan an-Nasa'i Book 6, Hadith 21 Next Hadith → "If any one of you catches the first prostration of 'Asr prayer before the sun sets, let him complete his prayer, and if he catches up with the first prostration of Fajr prayer before the sub rises, let him complete his prayer."

Sunan an-Nasa'i Book 6, Hadith 23