Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) said: "The Prophet (peace and blessings be upon him) entered the Ka'bah, and with him were Bilal, Usamah and Uthman, and he closed the door upon them." So I came and sat on the ground. They stayed in it for a long while. Then when the Messenger of Allah (peace and blessings be upon him) came out, I climbed the steps and entered the House and asked: Where did the Prophet (peace and blessings be upon him) pray? They said: "Here." And I forgot to ask how many rak'ahs he prayed.
Hadith Referenceالمعجم الكبير للطبراني / باب الباء / 1039