Narrated Nafi from 'Abdullah:

Allah's Apostle came to Mecca through its higher region on the day of the Conquest (of Mecca) riding his she-camel on which Usama was riding behind him. Bilal and 'Uthman bin Talha, one of the servants of the Ka'ba, were also accompanying him till he made his camel kneel in the mosque and ordered the latter to bring the key of the Ka'ba. He opened the door of the Ka'ba and Allah's Apostle entered in the company of Usama, Bilal and 'Uthman, and stayed in it for a long period. When he came out, the people rushed to it, and 'Abdullah bin 'Umar was the first to enter it and found Bilal standing behind the door. He asked Bilal, "Where did the Prophet offer his prayer?" He pointed to the place where he had offered his prayer. 'Abdullah said, "I forgot to ask him how many Rakat he had performed."

حَدَّثَنَا يَحْيَى بْنُ بُكَيْرٍ، حَدَّثَنَا اللَّيْثُ، قَالَ يُونُسُ أَخْبَرَنِي نَافِعٌ، عَنْ عَبْدِ اللَّهِ ـ رضى الله عنه أَنَّ رَسُولَ اللَّهِ ﷺ أَقْبَلَ يَوْمَ الْفَتْحِ مِنْ أَعْلَى مَكَّةَ عَلَى رَاحِلَتِهِ، مُرْدِفًا أُسَامَةَ بْنَ زَيْدٍ وَمَعَهُ بِلاَلٌ وَمَعَهُ عُثْمَانُ بْنُ طَلْحَةَ مِنَ الْحَجَبَةِ، حَتَّى أَنَاخَ فِي الْمَسْجِدِ، فَأَمَرَهُ أَنْ يَأْتِيَ بِمِفْتَاحِ الْبَيْتِ، فَفَتَحَ وَدَخَلَ رَسُولُ اللَّهِ ﷺ وَمَعَهُ أُسَامَةُ وَبِلاَلٌ وَعُثْمَانُ، فَمَكَثَ فِيهَا نَهَارًا طَوِيلاً ثُمَّ خَرَجَ، فَاسْتَبَقَ النَّاسُ، وَكَانَ عَبْدُ اللَّهِ بْنُ عُمَرَ أَوَّلَ مَنْ دَخَلَ، فَوَجَدَ بِلاَلاً وَرَاءَ الْبَابِ قَائِمًا، فَسَأَلَهُ أَيْنَ صَلَّى رَسُولُ اللَّهِ ﷺ فَأَشَارَ لَهُ إِلَى الْمَكَانِ الَّذِي صَلَّى فِيهِ، قَالَ عَبْدُ اللَّهِ فَنَسِيتُ أَنْ أَسْأَلَهُ كَمْ صَلَّى مِنْ سَجْدَةٍ