Abdullah bin Saaib used to lead Abdullah bin Abbas by the hand and position him at the third section of the wall near the door, on the side facing the Hijr.Ibn Abbas would ask Abdullah bin Saaib, "Did the Messenger of Allah ﷺ used to stand here, or pray here?"He would reply, "Yes."Then Ibn Abbas would stand and pray.
حدثنا يحيى بن سعيد عن السائب بن عمر قال حدثني
أن عبد الله بن السائب كان يقود عبد الله بن عباس ويقيمه عند الشقة الثالثة مما يلي الباب مما يلي الحجر فقلت يعني القائل ابن عباس لعبد الله بن السائب إن رسول الله ﷺ كان يقوم هاهنا أو يصلي هاهنا فيقول نعم فيقوم ابن عباس فيصلي
Its isnad is daif because of Muhammad bin Abdullah bin Saaib, whom they considered unknown. Abu Dawud narrated the hadith 2/181, no. 1900, in the Book of Rites of Hajj, chapter on the Multazam, with similar wording, and Nasai 5/221, no. 2918, in the Book of Hajj, chapter on the places of prayer around the Kaaba. See 15323.