Sayyiduna Abu Hurayrah (may Allah be pleased with him) states: On the day of sacrifice the Prophet (peace and blessings be upon him) said: "Whoever slaughtered an animal before the (Eid) prayer should repeat his slaughter."
Al-Bazzar recorded it; its chain contains a narrator, Bakr bin Sulayman al-Basri, whom al-Dhahabi declared thiqah (trustworthy), and a group narrated from him; the remaining narrators of this narration have been declared trustworthy.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الأضاحي / 5985