There was no horseman among us on the day of Badr except Miqdad. I saw us, and none of us was awake. All were sleeping except the Messenger of Allah ﷺ, who was beneath a tree praying and weeping until morning came.
حدثنا عبد الرحمن بن مهدي عن شعبة عن أبي إسحاق عن حارثة بن مضرب
ما كان فينا فارس يوم بدر غير المقداد ولقد رأيتنا وما فينا إلا نائم إلا رسول الله ﷺ تحت شجرة يصلي ويبكي حتى أصبح
Its isnad is sahih. It is found in Tabari's Tarikh 2/270, from Amr bin Ali, from Abdul-Rahman bin Mahdi. Hafiz bin Kathir also mentioned it in his tafsir 4:22, but attributed it to Abu Yaala, from Zuhayr, from Abdul-Rahman bin Mahdi. Perhaps the Hafiz forgot that it is found in the Musnad, so he did not attribute it there. It will also come again from Muhammad bin Jafar, from Shubah, 1161.