Abu Hurairah reported,

The Prophet ﷺ said, "When the prayer has been called to begin, there is no prayer except the obligatory one."

Azami 2441

Sahih

عن أبي هريرة

عن النبي ﷺ قال: إذا أقيمت الصلاة، فلا صلاة إلا المكتوبة.

الأعظمي 2441صحيح
Contents
Reference
Commentary
Ayat
Collection
Jami al-Kamil
Book
Prayer
Chapter
Sunnah prayers and voluntary prayers in general
Section
Dislike of being preoccupied with the two rakah of Fajr when the prayer has been called
Numbering
Jami al-Kamil 2441 (2nd edition)
Azami 2441