Nafi' (may Allah have mercy on him) narrates from Ibn Umar (may Allah be pleased with them both) that Salim (may Allah be pleased with him), the freed slave of Abu Hudhayfah (may Allah be pleased with him), used to lead the first Muhajirun and the Companions (may Allah be pleased with them) from the Ansar in prayer in the Mosque of Quba. Among them were Abu Bakr, Umar, Abu Salamah, Zayd bin Harithah and Amir bin Rabi'ah (may Allah be pleased with them).
The Shaykh says: Perhaps Abu Bakr and Umar (may Allah be pleased with them both) were present at another time, because Abu Bakr (may Allah be pleased with him) came with the Prophet (peace and blessings be upon him); or his leading them in prayer continued before and after the Hijrah, and the narrator meant the time after the Hijrah.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 5124
Nafi' bin Abd al-Harith al-Khuza'i (may Allah be pleased with him) met Umar bin al-Khattab (may Allah be pleased with him) at a place called Usfan. Umar (may Allah be pleased with him) had appointed him governor over the people of Makkah. He greeted Umar (may Allah be pleased with him) with salam, and Umar (may Allah be pleased with him) asked: "Whom have you appointed as your deputy over this valley?" He said: "I have come after appointing Ibn Abza as deputy." Umar (may Allah be pleased with him) asked: "Who is Ibn Abza?" He said: "He is one of our freed slaves." Umar (may Allah be pleased with him) said: "You appointed a freed slave as deputy!" He said: "O Commander of the Believers! He is a reciter of the Qur'an and knowledgeable in the shares of inheritance (fara'id)." Umar (may Allah be pleased with him) said that the Messenger of Allah (peace and blessings be upon him) said: "Indeed, Allah Almighty raises many people through this Book and brings many others low through it."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 5125
Sayyiduna Abu Sa'id (may Allah be pleased with him) narrates from the Prophet (peace and blessings be upon him) that he (peace and blessings be upon him) said: "When you are three on a journey, let one of you lead the prayer, and the one most entitled to lead is the one who has read the most Qur'an."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 5126