Musnad Ahmad 33:59

Muhammad ibn Ja‘far narrated to us, Sa‘id narrated to us, and [in another chain] ‘Abd al-Wahhab, from Sa‘id, from al-Walid Abu Bishr, from Talhah—‘Abd al-Wahhab al-Iskaf said: That he heard Jabir ibn ‘Abd Allah narrating: "That Sulayk came while the Messenger of Allah, peace and blessings of Allah be upon him, was delivering the sermon, so he sat down. The Prophet, peace and blessings of Allah be upon him, ordered him to pray two rak‘ahs." Muhammad said in his narration: Then he turned to the people and said: "If one of you comes while the Imam is delivering the sermon, let him pray two rak‘ahs and make them brief."