(28) CHAPTER. Whoever got (or was able to offer) one Raka of the Fajr prayer (in time) [One Raka means, one standing, one bowing, and two prostrations].
Narrated Abu Huraira: Allah's Apostle said, Whoever could get one rak`a (of the Fajr prayer) before sunrise, he has got the (morning) prayer and whoever could get one rak`a of the `Asr prayer before sunset, he has got the (`Asr) prayer.