Musannaf Ibn Abi Shayba 3:5434

7811. Abd al-A’la narrated to us, from Ibn Ishaq, from Sa’id ibn Abi Sa’id, from Sa’id ibn Marjana, who said: I sat behind Sa’d ibn Malik while he was performing the Duha (forenoon) prayer. He performed eight rak’ahs—I counted them—and he did not sit during them until he sat in the last of them. Then he recited the tashahhud, performed the taslim, and departed.