Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) narrates: The particular flag of the Prophet (peace and blessings be upon him) used to be with Sayyiduna Ali bin Abi Talib (may Allah be pleased with him), and the flag of the Ansar used to be with Sayyiduna Sa'd bin Ubadah (may Allah be pleased with him). When the fighting became intense, the Prophet (peace and blessings be upon him) would be with those who were under the flag of the Ansar.
Ahmad recorded it, and its narrators are the narrators of the Sahih, except for Uthman bin Zufar al-Shami; his case is different, and he is thiqah (trustworthy).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الجهاد / 9643
Hadith Gradingمحدثین:إسنادہ صحیح۔
Hadith Takhrij«اخرجه احمد فى المسند (3486) ، أخرجه مسند أحمد برقم: 3476»