Musnad Abu Ya'la al-Mawsili 42:131

Ubayd Allah ibn Umar al-Qawariri narrated to us, Makki ibn Ibrahim al-Balkhi narrated to us, from al-Ju'ayd ibn Abd al-Rahman, from Musa ibn Abd al-Rahman, that he heard Muhammad ibn Ka'b asking Abd al-Rahman ibn Abi Sa'id: "What did you hear from your father narrating from the Prophet, may Allah bless him and grant him peace?" Abd al-Rahman said: "I heard my father say: I heard the Messenger of Allah, may Allah bless him and grant him peace, say: 'The likeness of one who plays with dice and then stands to pray is like the likeness of one who performs ablution with pus and the blood of a swine.'" He said: "His prayer is not accepted."