Musannaf Ibn Abi Shayba 9:644

Abu Bakr narrated to us, from Ibn al-Mubarak, from Ibn Jurayj, who said: I said to 'Ata', "If a slave woman is emancipated and she immediately engages in sexual intercourse [with her former master], what is the ruling?" He said, "Evil is what he has done." I said, "Does she have the choice [to annul the marriage] over the free man?" He said, "No."