Sahih Muslim Book 19, Hadith Number 4415.

Chapter : The battle of Uhud.

It has been reported on the authority of Abu Hazim who heard from Sahl b. Sa’d. The latter was asked about the injury of the Messenger of Allah (may peace be upon him). He said: By God, I know the person who washed the wound of the Messenger of Allah (may peace be upon him), who poured water on it and with what the wound was treated. Then Sahl narrated the same tradition as has been narrated by ‘Abd al-‘Azlz except that he added the words: “And his face was injured” and replaced the word “Hushimat” by “Kusirat” (i.e. it was broken).