مَنْ أَدْرَكَ مِنَ الصَّلاَةِ رَكْعَةً فَقَدْ أَدْرَكَ الصَّلاَةَ ‏

(Muwatta Imam Malik, The Book of Jumuah)

Hazrat Abdullah ibn Umar ibn al-Khattab^(ra) used to say, “If the ruku has passed you by, so has the sajdah.” (Muwatta Imam Malik, The Times of Prayer)

Hazrat Abu Hurairah^(ra) used to say, “Whoever catches the ruku has caught the sajdah and whoever misses the recitation of the umm al-Quran [Surah al-Fatihah] has missed much good.” (Muwatta Imam Malik, The Times of Prayer)