It is narrated from Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) that the Messenger of Allah (peace and blessings be upon him) prayed at Mina without a wall or the like in front of him. Meanwhile I arrived, riding, and in those days I was close to puberty. I passed in front of the row, let the donkey loose to graze, and then entered the row, and no one objected to me.
Imam al-Shafi'i (may Allah have mercy on him) says: The words of Ibn Abbas (may Allah be pleased with them both), "towards something other than a wall", mean towards something other than a sutrah; and Allah knows best.
Imam al-Bayhaqi (may Allah have mercy on him) says: Malik bin Anas (may Allah have mercy on him) mentioned these words in this hadith in Kitab al-Manasik, and he narrated it in Kitab al-Salah without these words. Imam al-Shafi'i (may Allah have mercy on him) narrated it in his earlier view as it is narrated in Kitab al-Manasik, and in his later view as it is in Kitab al-Salah.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 3479