Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) narrates: I have seen the Noble Prophet (peace and blessings be upon him) always performing the prayer at its specified time, except for the case of Muzdalifah, because the Noble Prophet (peace and blessings be upon him) performed two prayers—Maghrib and 'Isha—together, and on that day he performed the Fajr prayer at a time different from its specified time. Sufyan says: That is, he performed it at a time different from the time in which he used to perform it previously.
Hadith Referenceمسند الحميدي / 114
Hadith Gradingمحدثین:إسناده صحيح
Hadith Takhrij«إسناده صحيح، وأخرجه البخاري 1675، ومسلم: 1289، وأبو يعلى الموصلي فى ”مسنده“ :5176، 5264، وأحمد فى ”مسنده“ ، برقم: 3711»