(It is narrated from Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) that) a man came to the Prophet (peace and blessings be upon him) and asked him about a man who takes the ritual bath (ghusl) for major impurity (janabah) but the water misses some part of his body. The Messenger of Allah (peace and blessings be upon him) said: "He should wash that place, then pray."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 10515