Sayyiduna al-Fadl bin Abbas (may Allah be pleased with him) reported that he entered the House (the Ka'bah) with the Prophet (peace and blessings be upon him), and that the Prophet (peace and blessings be upon him) did not pray inside the Ka'bah when he entered it; but when he came out, he prayed two rak'ahs by the door of the Ka'bah.
Hadith Referenceالمعجم الكبير للطبراني / باب الفاء / 15834