Shama-il Tirmidhi Chapter 040, Hadith Number 003 (274).

'Abdurrahmaan bin Abi Layla RA. (a Taabi'ee) reports: "None had given me the news that they had observed Rasulullah Sallallahu 'Alayhi Wasallam perform the salaatut duhah besides Ummi Haani. She said: Rasulullah Sallallahu 'Alayhi Wasallam came to her house, the day Makkah was conquered. He performed ghusl (bath), then performed eight rak'ahs. I did not observe Rasulullah Sallallahu 'Alayhi Wasallam perform any salaah shorter than these, despite him performing every ruku' and sajdah properly"'. (He did not perform the ruku' and saidah haphazardly because the salaah was short).

Commentary
'Abdurrahmaan RA. saying that none besides Sayyiditina Ummi Haani Radiyallahu 'Anha narrated this hadith, does not necessarily mean that no other Sahaabi knew about this. In this chapter the narration of a few Sahaabah Radiyallahu 'Anhum are mentioned. Ibn Jareer RA. says: 'So many ahaadith have been narrated on salaatut duha that it reached the stage of tawaatur (unbroken chain of authentic narrators). It has already been stated that nineteen Sahaabah Radiyallahu 'Anhum narrated about this salaah. It may be that those people did not have information that from whom did 'Abdurrahmaan RA. investigate about this salaah. There is no perplexity in this. Some 'ulama are of the opinion that the salaah mentioned in the hadith under discussion, was not the salaatut duha, but a prayer of thanks on the conquering of Makkah. It was the practice of Sayyidina Rasulullah Sallallahu 'Alayhi Wasallam when an event of happiness occurred, to perform salaatus shukr (prayer of thanks-giving). It may also be possible that these eight rak'ahs included both the Salaatut duha and salaatus shukr.