Chapter: The ruling on semen
Amr b. Maimun said: I asked Sulaiman b. Yasar whether the semen that gets on to the garment of a person should be washed or not. He replied: A'isha told me: The Messenger of Allah ( صلی اللہ علیہ وسلم ) washed the semen, and then went out for prayer in that very garment and I saw the mark of washing on it.
Authentic