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 ﷺ washed the semen, and then went out for prayer in that very garment and I saw the mark of washing on it.
عَنِ الْمَنِيِّ يُصِيبُ ثَوْبَ الرَّجُلِ أَيَغْسِلُهُ أَمْ يَغْسِلُ الثَّوْبَ فَقَالَ أَخْبَرَتْنِي عَائِشَةُ أَنَّ رَسُولَ اللَّهِ ﷺ كَانَ يَغْسِلُ الْمَنِيَّ ثُمَّ يَخْرُجُ إِلَى الصَّلاَةِ فِي ذَلِكَ الثَّوْبِ وَأَنَا أَنْظُرُ إِلَى أَثَرِ الْغَسْلِ فِيهِ