Sayyiduna Ali bin Abi Talib (may Allah be pleased with him) narrates: We went with the Prophet (peace and blessings be upon him) to a man of the Ansar who had a swelling. The Prophet (peace and blessings be upon him) said: "Will you not drain it out of him?" The narrator says: So it was lanced while the Prophet (peace and blessings be upon him) was watching.
Imam Abu Ya'la recorded it. Its chain contains Abu al-Rabi' al-Samman, and he is da'if (weak).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الطب / 8376