Sayyiduna Umar (may Allah be pleased with him) wrote to Sa'd bin Abi Waqqas (may Allah be pleased with him): I am sending you some people as reinforcements. Whoever of them reaches you before the bodies of the slain burst open, give him a share in the spoils.
Imam al-Shafi'i (may Allah have mercy on him) says: This is not established from Sayyiduna Umar (may Allah be pleased with him). If it were established, we would quickly accept it. Then he mentioned how Abu Yusuf contradicted this hadith of Sayyiduna Umar (may Allah be pleased with him).
The Shaykh says: It is munqati' (broken), and its narrator Mujalid is da'if (weak). The chain of the hadith of Tariq bin Shihab (may Allah be pleased with him) is sahih (authentic); there is no doubt about it.
Imam al-Shafi'i (may Allah have mercy on him) says: Something established has been narrated from the Messenger of Allah (peace and blessings be upon him) on this, in agreement with what is narrated from Sayyiduna Abu Bakr and Sayyiduna Umar (may Allah be pleased with them both), but I did not remember it well.
The Shaykh says: Perhaps he meant the hadith of Sayyiduna Abu Hurayrah (may Allah be pleased with him) containing the incident of Sayyiduna Aban bin Sa'id bin al-As (may Allah be pleased with him): when he came to the Prophet (peace and blessings be upon him), he had already conquered Khaybar, and he did not give them a share. This has passed earlier in "Kitab al-Qasm", along with what is narrated on it.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب السير / 17955