Narrated `Aisha: I used to wash the traces of Janaba (semen) from the clothes of the Prophet and he used to go for prayers while traces of water were still on it (water spots were still visible).
Hadith ReferenceSahih Bukhari / The Book of Wudu (Ablution) / Hadith: 229
Hadith Gradingمحدثین:أحاديث صحيح البخاريّ كلّها صحيحة